Sleep schedules at 3 months - what worked for you guys?

Daughter is 3 months old now and sleep is still all over the place. She'll sleep 4 hours then be up for 2. Wife and I are tag teaming but we're wrecked. I keep reading about sleep training but feels too early. What did you guys do? Did you just let it happen naturally or did you try to establish a routine? Any advice that actually worked? We're considering swaddling different, white noise machine, the whole thing.