If you match, you can still be on the WL for any schools you had ranked higher than your match school.
If you don't match, watch your emails because most schools will notify you that you are on their WL, or perhaps ask you if you would like to be on their WL. Be sure to respond or confirm.
This can take a week or two to happen, because our TMDSAS Match Day takes place at the same time as NRMP Match for MS4 students and the med schools will be spending some time supporting their students through the residency match.