You only need to do the steps with the cups once. The reason is that this manifestation method makes use of reality shifting concepts. You should think of the process like walking through a gate. You do not need to pass through a gate over and over to get a result. Walking through it once is enough. But what matters is to maintain that belief after the method is done.  The moment you feel you can't sustain the belief anymore, then you certainly can repeat it in the future if you want.