How to get 6.5 month old baby to nap?

My 6.5 month old baby has been an awful napper pretty much his entire life. The only thing that has worked is contact napping in a carrier, car seat, and stroller. I have tried rocking to sleep and transferring, he wakes up with the slightest movement, even if I wait awhile, I have tried putting him next to me in a bed, he doesn't get that concept either. I ensure he is full and has a clean diaper. Luckily he is a good nighttime sleeper but I think that's because we have had a good routine and he has been in his own crib/room at 2 months. Any advice on how to get baby to nap in crib?