Skateboardingpunk420

You should make your cut after your plant has grown 4 or 5 nodes. Just crop off the new growth leaving about 1/8 to 1/4" of growth above the top node. Your plant will then go into a little stress, sometimes no stress at all, for a few days and then it will start to grow two "tops" in place of the one that was growing.

I hope this helps.

Peace