Keep at it, seriously! You CAN do this.
I don't know if this is the problem you're encountering, but it was mine and was very frustrating, so here goes: the best advice that I can give is to keep knitting on one piece--no matter how hideous you think it looks, don't keep ripping it out and starting over. The reason is that when you've just started knitting, the first few rows look absolutely disgusting. They don't have definition and appear not to be knitting at all; however, they are. I grew so weary of casting on that I made myself keep going without starting over. After a few inches, the stitches started to look, well, like stitches! And after a few inches more, the rows started looking more uniform as I got into the rhythm of knitting and figured out what the best way was for me to hold the yarn and needles.
Just don't give up. Please! And you'll find all sorts of help here, so don't hesitate to ask!