Duffers Guide to Betting

1. Bookmakers.
The most popular and simplest way of placing a bet is with one of the fixed odds bookmakers. These are the names that I'm sure most people have heard of . Ladrokes, William Hill, Corals and Paddy Power,being the most well known.
The prices offered by these bookmakers generally only change once or twice a day. If at all
The second type of 'bookmakers' are the betting exchanges, the most well known and biggest being betfair.com . These exchanges act much like the stock market,with the prices offered changing in real time. Often every second or so. With betting exchanges you can also be the bookmaker and take other peoples bets, also known as laying. More about this later.

2. Odds
There a 2 ways of expressing odds. Either fractional or decimal.Most Bookmakers use fractional, but the betting exchanges use the decimal method

Fractional Odds - Well if you remember your fractions from school then you're virtually there.
In very simple terms you have to put on the 2nd number to win the 1st.
Some examples- 2/1 . Place a bet of £1 and you win £2 plus your £1 back. So you'll receive £3....or £2.50 on at 2/1 and you'll win £5 plus your stake back. Return of £7.50.
A slightly trickier example, 4/6. You have to put on £6 to win £4 plus your £6 back,giving you a return of £10......or £10 on at 4/6 would give you winnings of £6.67 plus your stake back. A return of £16.67.

Decimal Odds - Betting exchanges and some fixed odds bookmakers use this method.
Basically all you do is multiply your stake by the number quoted to work out the money you get back
So if you had a bet of £4 at 3.2 (4 x 3.2 =12.8) a return of £12.80. Note that this includes the return of your stake.
In the 2nd example above,4/6 would be expressed as 1.67 under the decimal method

3. Betting on the exchanges.
Rather than me trying to explain it, a full explanation is here
Including the mysterious art of laying