Now this seems to have worked for me.
I went through topcashback.co.uk as I am in the mode to using that recently although this deal is also on quidco.
So click through either cashback site, and then create a new bingo account load up £10 try to win ( I failed) spend all of the £10. Then wait for a short while and topcashback tracks !
Bargain = £10.20 ( topcashback are upping by 1% at the mo) for FREE.
Be aware if you win money, they charge a £5 fee if the amount you withdraw is under £30. But that said you can just go for it, spend the £10 in one go and be quids in.