just choose options that relate to him!! dont tell the npcs about him at the start, and what i usually do is choose the study room event then go with deja, jamie, and cam, choose to go to the thrift store and look at clothes with jamie, then just choose options favored towards him after that.
im nottt sure if this is 100% but it might help to have a fall mc from my experience?? at least that makes him text you at the start more often but idk if it impacts the rest of the game