i like to 'face' irregular edges. it takes more fabric but i feel that it stabilizes the bias edges better. i cut with the grain and piece as i need to, so i can use up odd bits if necessary, even different colors. i overlap the pieces instead of connecting them and flip them to the wrong side for hand stitching. where the two facing pieces overlap, i slip-stitch or ladder stitch those as well. it's also a good place to slip in a colored flange if you feel ambitious.