I use www.tradindex.com you can set up a fantasy account which i did for a month or two. I made £500, but once you put your actual money in, it changes the perspective on the whole lot.

Only put in what you can afford to loose.

You need to put in a certain amount to cover yourself if the market jumps quickly and you miss it. You can also put a stop at a certain point so you only loose so much if it goes the wrong way.

I put in £400 and that allows me enough room to place £1-£2 bets