Tie it first. I use crochet thread and tie a square knot (right over left, then left over right) so that it won't come untied. Or . . . . if you have fancy stitches on your sewing machine, you can use a little round buttonhole or a star. I've done that before and it really works well. If you'd rather not have the ends of the ties (and--just as an aside--Downy quilts won't allow it) sticking up, it's another good option.