How do you improve your poker skills?

[Sgt. Pepper the Cubs fan]

Now before I really say anything I don't play cash games. I normally just play for free and stuff. One problem I notice is that I usually get to the point where I can't keep up with the blinds because they keep getting raised. One thing I read though was that you should not play to many hands and that if you are dealt poor pocket cards you should just fold them for instance if you get a 2 and 7 off suite that is something you should fold. I normally do that, but sometimes I am dealt things that appear bad but in the end I would have folded the best hand. I guess I also need to work on being more aggressive when I have something good instead of calling I should raise, or I should bet instead of check, I am not sure what tips would be good to get better. The thing is though keep in mind it is free so sometimes people will go all in on the first hand pre-flop which I would refuse to do.
Yeah cause Kenny Rogers can offer poker advice.