Usually you have to find the store. I would contact the store you to transfer to and find out what their process is, do they have an opening, what their business is like etc. Establish a relationship with that SM. Some stores may have you apply for the position. Either way having all the info far ahead a time is to your benefit. Even when all looks good and both sides agree it’s going to work, since it’s months in advance, keep in check/updated with both stores. I’ve seen people partners fall through the cracks because SMs or DMs kept playing phone/email tag.