Night time potty training

I began potty training my 2 yo the day after his second birthday. He’s 2 years and 2 months now. It’s been about a month since his last accident and he just recently began pooping in the potty also. When is a good time to begin night training him? And how the heck do you night train? He wakes up in the morning and after his nap with a fully loaded wet diaper. I should note that he also drinks about 9 ounces of breast milk before bed and before naps.