My current challange

I have been given $50 to play on Tony G's poker site, so I have decided to try and improve my non existant cash game skills. I have been playing 0.05/0.10 NL Hold'em tables. The first couple sessions I was throwing a way money and then scraping it back again. I am currently sitting with $79.56, which doesnt seem to bad. I am somewhat conscious of what levels I am playing at, especially when to move up a level. The figure that comes to mind is $150, i might give 0.10/0.25 tables a go then.