It will make the process easier. All folds should be sharply creased. It helps to go over the fold with a fingernail on a flat, hard surface. Start by folding about the width of the white border on one end of the bill. Keep folding back and forth, with each fold the same width.
Consistency really improves overall appearence.
For clarity, this is an end view showing what I mean by folding back and forth . Once you've finished the entire length of the bill, pinch one end and bend it over as shown. This will keep the 'handle' end closed quite nicely. All that's left is to spread the folds out on one side. Just like ordinary paper fans, the outside edge is all curved over in one direction to give it a little stiffness.