| Everyone has their own idea of how tight or loose a well-fitting waistband should be. Cut your waistband piece your waist measurement plus SA, plus overlap (and underlap if you like) plus a little extra. When it is time to apply your waistband, take your waistband piece (interfaced) and fold as it will be. Place around your waist, pinning in the back when it is comfortable. Mark the CF and side seam lines where they will be on you. Mark the CB before removing.
Now you can pin it onto your garment, matching CB, CF and side seams. You should have some to ease in, over the tummy at least. Finish your ends now if you wish, then stitch to garment, turn, and stitch in the ditch, topstitch or handstitch. I use a hook on the overlap and a snap on the underlap. If you use both over and underlap, future alterations are so much easier.
This method gives me very comfortable waistbands which fit well. I like a narrow waistband, so I am most sure of this method for that look.