HELP

I feel like my 6 month old couldn't be sleeping worse. He takes bad naps (30-40 mins with the occasional 60-120 mins), goes to bed early (6pm is our goal but sometimes we can't even make it to that time), wakes throughout the night (every 1-2 hours to feed) and starts his day around 5am. Please help me figure out what I need to be doing. Because of the bad cycle we're on he can barely make it to 2 hour wake windows so we're usually doing 4 naps. He's also a snacker so I think he's waking in the night genuinely hungry. I tried the 5/3/3 but he just doesn't go back to sleep and gets hysterical unless I feed him. The one positive thing is we did CIO at 5 months so he is pretty good at getting himself to sleep initially. He was born a month early so i've always given us some slack but I think I can safely say things aren't just going to sort themselves out at this point.