Declan, the real thing about betting is that broadly the odds are normally 'about right' but slightly in favour of the bookmaker on Betfair they are probably more equal. But effectively the probability is about right. So to gamble successfully (traditionally -ie not trading) you need to look where you think the bookies have got their probability wrong - that is called value - and then go big. This takes a combination of balls, a knowledge better than the market maker and a bankroll ( a serious gambler will stack big on something that they think is priced wrong but offers value ie their probability = 6/1 the bookies 8/1 then in the long run this is likely to be a profitable play but requires a bankroll). To illustrate a professional gambler if offered 2/1 on a coin flip on the proviso they had to bet at least ?10,000 pounds would take it no problem, it's value...would you if you had it as spare cash? there are exceptions to the market being about right IE England are always a stupidly short price for World Cups because so many people put money on them, and these offer opportunities too.