Get on well with other college students who don't share a room. Generally, the short-term relationship should be above 50, and the long-term relationship should not be too low. Then they will have the option of "asking for loyalty" and then there will be a probation period. As for how long it will take, it depends on how long it will take you to contact them for the second time. This is called recruitment.

If your computer is equipped enough, you can also invite them to live here directly, so that they can join your club directly without the option of "asking for loyalty".