I always use a walking foot to attach my binding and I never press or pin my binding. I just fold it as I go along and guide it along the edge of my quilt. I do stitch the edge of my quilt before hand using a 1/8+ seam. This holds the layers of my quilt stable. Sometimes I will use a bias binding and other times a straight of grain. I start with a 2.25" strip. The width of my walking foot is 3/8" so I use that as a guide rather than 1/4" seam. This means that I am stopping 3/8" at the corners to miter them. I use a different method to join the final ends in a miter. The method I use has leaving a tail at the starting and ending point and folding each tail back so that there is about 1/8" gap between the two folded ends. You cut at one fold and then use that cut piece the width of the binding (in my case 2.25") to measure from the other fold to cut the other tail off. You then bring one cut end perpendicular to the other and sew a miter. I know this sounds confusing but the bottom line is that my unsewn strips of binding after I cut them are a tad shorter to allow for the stretching that occurs when you join your miter. This works for me every time and I don't have puckers.