There are so many methods, and it really depends on how you want to approach it. I typically TT one day at a time until I get a ping for someone to move. If he refuses to move out, I suggest trying to get your friendship with him really high by daily interactions, doing his requests when possible and sending him letters. I've found that this method worked best for me for the stubborn ones although Freya did give me a run for my money for 3 years, she would ping and when I said bye, she would say something along the lines of wanting to be better friends with me lol.
But here is a guide that could help you,
LINKED HERE.