Before you rush to open an account, here's my advice:
Never gamble more than you can cheerfully afford to throw in the gutter. If you're playing with money you can't afford to lose, you'll 'play scared' and make emotional decisions... which almost guarantees you'll get wiped out fast...
To start spread betting the financial markets, it is worthwhile reminding ourselves of the basics of share trading:
We should expect that a stock will either rise or fall in value
Shares are bought in the expectation they will rise in value so they can be sold at a profit. This is known as...