I used swaddle, and play soft music, make sure room is dark and not too warm. I also pay attention to his sleep cues (yawning, sleepy look, rubs eyes), and time his naptimes. At 2.5 months, I usually put him to sleep after he’s been awake for 1.5-2 hours. It does take effort to track, and help the baby to establish a routine. But once the routine is there, it’ll be much better. In fact, the more he sleeps, the better he sleeps. Overtired babies are hard to coax, cranky, and harder to put to sleep too - so beware of that as well.
Yan Bing