The text below has been taken directly from Camelot's leaflet 'HOW TO PLAY THE NEW GAME THUNDERBALL', which is freely available from National Lottery retailers. Just to be clear, although this is an unauthorised copy of the leaflet, I am in no way claiming any ownership of, or credit for, the following text, which has been reproduced here solely for the benefit of my visitors.

Quick Guide

Play this new game from The National Lottery and you'll find it's the 'Thunderball' that makes all the difference. For example, match just one ball plus the "Thunderball" and you're a winner. If you match 5 main balls you win £5,000*; however match the 'Thunderball' as well and you can turn your £5,000* win into a £1/4 million* windfall.

*Depending on the number of winners overall and per prize category, prizes may on occasion be less than stated.

To experience the thrill of the 'Thunderball', follow these simple steps:

1. CHOOSE YOUR NUMBERS
Using the first board on The National Lottery Thunderball Game Play Slip, choose 5 numbers from 34 in the top box marked 'SELECT FIVE', and then your one 'Thunderball' from the 14 numbers in the box below marked 'SELECT ONE'. To have your numbers selected randomly, tick the 'Lucky Dip' box or ask your retailer for a Thunderball Game 'Lucky Dip'. You can choose to play up to 5 boards on each Play Slip if you wish. The cost is £1 per game. There is also the opportunity to play in groups.
(See 'Playing in a Group' below.)

2. MARK HOW MANY WEEKS
You can pay and play for up to 8 weeks in advance. Just mark the 'No. of WEEKS on the Play Slip.

3. CHECK YOUR TICKET
After you have paid and handed in your Play Slip at the counter, you will be given your ticket for The National Lottery Thunderball Game. Please check that all details are correct and write your name and address on the back. If you need to cancel your ticket, please see below for details. Important: You must have your ticket to claim any prize. Please keep it in a safe place!

4. EIGHT WAYS TO WIN

*Depending on the number of winners overall and per prize category, prizes may on occasion be less than stated.

5. FINDING OUT IF YOU'VE WON
You can wait for the 'Thunderball' to roll every Saturday night on the televised draw or check most other national broadcast TV, text services and radio stations for the winning numbers. Results can also be found in national newspapers, on the web at www.national-lottery.co.uk and at all the places you'd normally buy National Lottery tickets. You can also call The National Lottery Line on 0845 9 100 000 at the price of a local call (except from a mobile telephone). Alternatively, simply have your ticket checked at the terminal of any National Lottery On-Line outlet.

Tickets can be purchased up until 7.30pm each Saturday to be included in that Saturday's draw.

6. CLAIMING YOUR PRIZE
Cash prizes up to £75 can be claimed at any National Lottery On-Line outlet.
(For full details see below.)

ANNOUNCING YOUR WIN
If you would like people to know that you are a winner, we will take care of the publicity for you. However, if you prefer to keep the good news to yourself, we will take all the steps we can to protect your privacy.

FOR THE GOOD CAUSES
It's worth remembering that every time you play The National Lottery Thunderball Game you are helping The Good Causes. (For full details see below.)

REMEMBER!
You must be 16 years or over to play The National Lottery Thunderball Game or claim a prize.

For full details on 'How To Play', see below.

Full Guide

1. CHOOSE YOUR NUMBERS
The National Lottery Thunderball Game Play Slip has 5 boards on it. Each board consists of 2 boxes. One box (marked 'SELECT FIVE') contains numbers 1 to 34 from which you select five numbers. The other box (marked 'SELECT ONE') contains numbers 1 to 14 from which you select one number. If you'd like the terminal to choose your numbers at random, mark the 'Lucky Dip' box on each of those boards on which you wish to play 'Lucky Dip', or simply ask the retailer for a 'Lucky Dip'. (Note: You should not select a set of numbers and mark the 'Lucky Dip' box on the same board.) If you wish to make another selection, use another board. Each board will cost you £1.
Only use a pencil or a blue or black pen. Put a clear, bold, vertical line through each number you have chosen. If you make a mistake, mark the 'void' box and use another board.

2. CHOOSE THE NUMBER OF WEEKS TO PLAY
On every Play Slip, you'll see a section called 'No. of WEEKS' which lets you use the same set of numbers for up to eight weeks, starting with the next available draw. You must pay for your required number of weeks in advance. Here's an example of how it works. Let's suppose you have filled in 4 boards on your Play Slip and you would like to play these same numbers for 3 weeks. Simply mark the '3' box in the 'No. of WEEKS' column. For this example, 4 boards for 3 weeks will cost you £12. When you give your Play Slip to the retailer, he or she will give you a ticket that will enter you into every Thunderball draw for the next 3 weeks. It's that simple.

3. GET YOUR TICKET
When you've paid, the retailer will enter your selections into the terminal and give you a Thunderball ticket. You must check that the numbers you have selected, the number of weeks and the draw date(s) are correct, that the barcoded serial number is clearly readable and that the 'void' box on your ticket has not been marked. Then write your name and address on the back. Keep your ticket safe, you'll need it to check off your numbers in the draw. Don't lose it! You'll need it to claim your prize, as it is the only proof that you are a winner. If you need to cancel an On-Line ticket, you must return it to the Lottery terminal from which it was purchased within two hours or, where earlier, before the retailer or system closes for the night or a draw break.

4. HOW TO WIN
If the first five numbers in any one six-number selection on your ticket match in any order the five main numbers that are drawn, and the Thunderball number in the same selection matches the Thunderball number drawn, you are a top prize winner. You can also win by matching other combinations of numbers. See the table below.

Winning Selections           Odds           Prize Value*
Match 5 & the Thunderball    1:3,895,584    £250,000
Match 5                      1:299,660.3    £5,000
Match 4 & the Thunderball    1:26,866.1     £250
Match 4                      1:2,066.6      £100
Match 3 & the Thunderball    1:959.5        £20
Match 3                      1:73.8         £10
Match 2 & the Thunderball    1:106.6        £10
Match 1 & the Thunderball    1:32.8         £5
Any Prize                    1:18.2

*Depending on the number of winners overall and per prize category, prizes may on occasion be less than stated above. This will happen when the total value of prizes, which would otherwise have been paid, exceeds the total sales for that draw, and the number of prizes in any category, exceeds the maximum number of prizes for that category, as specified in the Game Procedures available from all National Lottery On-line retailers or The National Lottery Line.
If this happens, the prize amounts in such category/ies will be reduced as specified in the Game Procedures, so that the total value of prizes does not exceed total sales for that draw.
Due to the fixed prize nature of this game there are no Rollovers if the top prize is not won.

5. HOW DO YOU KNOW IF YOU HAVE WON?
As well as the televised draw, you'll find the winning numbers in national newspapers and available from all National lottery On-Line retailers. The winning numbers for previous draws can also be obtained by calling The National Lottery Line on 0845 9 100 000 (calls normally charged at the local rate in the UK except on mobile phones) or on the internet: www.national-lottery.co.uk

6. CLAIMING YOUR PRIZE
If your prize is up to £75, you can claim it in cash from any National Lottery On-Line retailer. All you've got to do, is give them your winning ticket to validate through their Lottery terminal. The terminal will then produce a validation slip which will show the value of your prize. Check this against the amount paid out and return it to the retailer. At their discretion, all retailers can pay prizes up to £ in cash.
Some National Lottery retailers are authorised to pay prizes of up to £500. National Lottery Post Offices will pay out prizes of up to £10,000, though prizes over £500 will be paid by cheque.
Anything above £10,000 must be claimed in person from a National lottery Regional Centre and will be paid by cheque (no cash is held on these premises).
If you match the 5 main numbers and the Thunderball number, please call The National Lottery line immediately for assistance in claiming your prize. Ring 0845 9 100 000 (calls normally charged at local rate in the UK except on mobile phones).
To claim any prize above £500, you will have to complete a Prize Claim form (available at National Lottery retailers or by phoning The National Lottery Line) and provide proof of your identity. If you are claiming a large prize, additional checks on your winning ticket may be conducted. All National Lottery prizes must be claimed by llpm, 180 days after the winning draw.
You can also, at your own risk, claim your winnings up to £10,000 by post. Send your winning ticket and the completed Prize Claim form to this address: The National Lottery, Accounts Dept, PO Box 287, Watford WD1 8TT
Remember, The National Lottery accepts no responsibility for tickets lost In the post.

7. PUBLICITY
If you are a winner, The National lottery will only reveal your identity if you give written consent to publicity. It's important if you have won a major prize to telephone The National Lottery Line immediately and certainly before you tell anyone else, so that we can advise you on your publicity options.

8. FUN FOR YOU, FUNDS FOR GOOD CAUSES
Don't forget, every time you play The National Lottery, you help a good cause. About 28% of The National Lottery proceeds will, over the period of Camelot's operating licence, go to the six Good Causes -the Sports Councils, the Art Councils, The National Lottery Charities Board, the Heritage Lottery Fund, the New Opportunities Fund and the Millennium Commission which has been set up to help celebrate the advent of the year 2000.

9. THINGS TO REMEMBER
You must be 16 years or over to play Thunderball or claim a prize. You must have purchased your Thunderball Game ticket by 7:30pm on the day of the relevant draw, to take part in the draw. Information about The National Lottery Games, including the Player Code of Practice, is available at all National Lottery retailers. If you are unable to get to a National Lottery retailer, call the National Lottery Subscription Line on 0845 1 250 000 and ask for information on the subscription service (calls normally charged at the local rate in the UK except on mobile phones).

Your National Lottery Regional Centres are located in:

Ask your National Lottery retailer for the full address.

If you have any questions or complaints about The National Lottery, ask your National Lottery retailer or phone The National Lottery Line on 0845 9 100 000 (calls normally charged at the local rate in the UK except on mobile phones). Or you can write to this address: The National Lottery, PO Box 1010, Liverpool L70 1NL. For the hard of hearing using Minicom equipment, please call 0845 9 100 045.

NOW YOU KNOW NOW, THERE'S NOTHING TO STOP YOU PLAYING. REMEMBER THE NEXT THUNDERBALL TOP PRIZE WINNER MAY JUST BE YOU.
*The National Lottery Thunderball Game is subject to the Rules for On-Line Games and The National Lottery Thunderball Game Procedures, (as amended from time to time).
In the event of any discrepancy between this leaflet and the Games Rules and Procedures (as amended from time to time), the Games Rules and Procedures apply. The Game Rules and Procedures are available at National Lottery retailers or from The National Lottery Line.

Playing in a group can increase the fun and excitement of playing The National Lottery Thunderball Game. Groups can be made up of friends, family or work colleagues. It's a great way of playing The National Lottery Thunderball Game and by following a few simple guidelines playing should be easy and enjoyable.
For example, let's say you and nine of your friends decide to form a group, putting in £1 a draw each. Instead of your £1 buying one set of six numbers you'll have an equal share in ten sets of numbers, giving you ten times more chances of winning a prize. So if your group won a jackpot of £250,000 your share would be £25,000.