Best advice - there are lots of options for this particular topic, but here are the ones that finally put me at ease about my piecing and quilting.
* Don't watch the needle go up and down when you sew. The needle doesn't go left or right, only up or down.
* When I stopped watching the needle 'up/down' and started paying more attention to guiding the fabric under the needle accurately, my piecing got much, much better.
Over time, I've also recognized my strengths, weaknesses, likes and dislikes, general ability and, best of all, my creativity - in other words, I found my 'style'. That has allowed me to have fun with quilting, and that is what it's really all about!