Use the colors and fabrics suggested in a pattern in a book and go with them. If you like the one pictured there is no reason yours shouldn't look the same. Some have more artistic talents in choosing colors and texture, the rest of us do our best and I have never seen a quilt I didn't like. Just like Will Roger said, he never met a man he didn't like.
You have to start liking your own work and not being critical. None of us is perfect.
Carol J.