I try to split my writing down into sections - first edit, then put aside for a while, then come back, finalize piece and post. I'm usually working on other pieces during the "put aside for a while" stage. By the time i have come back to Piece 1, I'm readig it again with fresh eyes. By the time I've done that, I can look at the new pieces with fresh eyes.
You have got to enjoy what you write. It is tough, especially if you want to get work out there, so knowing you enjoy what you do will help. I also think it shows through in the writing too and people pick up on it.