How to get 2 year old with autism to sleep

My son is about 28 months or so and his sleeping schedule is the absolute worst. He’ll go to sleep at 1-2am and wake up 3 hours later and stay up. He won’t go back to sleep for another few hours after that. I honestly have no idea what to do. He’s nonverbal so I have no way of communicating to him that he needs to lay down, relax and try to sleep. When he wakes up he’ll get in my bed (I room share) and scream for what feels like hours until he gets soemthing to be entertained with. Whether it’s a toy or my phone. I’m having baby number 2 in under 30 days and I cannot imagine myself having any form of sleep with a newborn sleep schedule and with his sleep schedule. Any advice at all would be appreciated.