Hi there!
Congrats on your DS! First things, please be sure to read the EASY routines for 0-3 months. What I would recommend is that you start a 3 hour routine with your LO.
The most important part is that you always start your day at the same time. It is important that you pick a starting time, wake him up and feed him (E), give him awake time like in the bouncer seat, or under a baby gym, then after about 1.5 hours put him down for his nap. You should repeat that every 3 hours.
I will wark you, you will have to train him to sleep. That means long periods of pat/shh over the crib if he cries. However I garauntee you that it will pay off! If you are consistent in the routine it will work and luckily at his age only a few days and he should be right in the routine.
It should look something like:
E 7 am Wake up and feed (breastfeed or bottle)
A 7:30-8:30 - activity, change diaper
S 8:30 - put him down for nap (follow sleepy cues if he shows them earlier)
E 10 am Wake him up and feed
A 10:30 - 11:30 activity and diaper change
S 11:30 - put him down for nap
E 1 pm Wake up and feed
A 1:30-2:30 activity and diaper change
S 2:30 - put him down for nap
E 4 pm wake up and feed
A 4:30-5:30 activity
S 5:30 or 6 45 min cat nap
E 7 pm feed him (9 pm if cluster feeding)
A 7 pm activity, bedtime routine, bath etc
S 7:30 pm bedtime
E 10:30 or 11 pm dreamfeed
I will say that usually if a baby is resisting naps hard then they are actually overtired. It is important that you learn your baby's sleep cues and that you do the 4 S routine as soon as you see the first sign of sleepyness. Swaddle, sit, shhhhh him (if needed) and put him down.
I wish you luck!