Correcting bad habits...

Recently, I've noticed a few habits that I probably need to correct.  Sometimes I realize that my right foot is rolling or inverted.  Not good.  And, occasionally I think I'm leading my pedaling with my toes too much.  Every once in awhile I can just barely feel my left toe clip graze the ground.  Probably not good, either.  So, I'm trying to be more conscious of keep my feet straight on the pedals and in the clips.  And when I do that, I immediately notice an increase in the power of my pedaling.  I should probably read up on some good form tips, that would be helpful.