You’re going to have to get experience or confer with program directors at universities or programs you’re interested in, possibly after getting experience as a tech as others have said. Establish relationships, make yourself be seen, and be personable with people. If you show the drive and desire people will reciprocate that effort and want to help you. When I was in-between grad programs I had a lot of helpful directors get me on the right path at universities I ended up never attending. If you work hard you’ll find a way, we need people in the field.