Well, I generally cut wof first to keep from coming up short. You will be cutting your 38" piece in half to make your 2 handles. Which means they will be roughly 15-151/2" when attached to your bag. It is up to you, if that is long enough. If not, do you have enough of one of the other fabrics that you used for your bag? You could cut handles from it. Or, instead of a bag that you can put over your shoulder, you would maybe be just as happy with shorter handles.