£50 is returned as cash. I usually go for >1 goal, which at the moment is 1/25 = £52 return. Current best odds on 0-0 are 12/1 to lay it off. Put about £4 on that, most you can lose is a couple of quid.
I had Man City 3-1 Liverpool last time, would have won about £700 but bottled it and cashed out for nearly £500. Nearly won £150 on the CL final too until Real equalised in the last minute.
http://www.bet365.com/extra/extra.aspx?ContentPath=Promotions%2cSoccer%2cPremierLeagueFreeBet