I used to have those problems with applique. Two things really helped me. The first was in Hamilton, Montana, while at one of my favorite small quilt shows in the world, I asked one of the quilters who had a demonstration set up what her secret was...the first, she said, was to use Steam2Seam; and the second was to stitch very slowly; and the third, to practice, practice, practice; the second was in getting the book Machine Applique for the Terrified Quilter. Her advice, plus this book, have really helped improve my applique. I frequently use the blanket stitch on my machine for this type of applique. Good luck!