Ronnie, I just looked at pictures of your press and it doesn't look like it has micro registration - which is a bit of a pest.
Anyway - make a print of your design and tape it to your platen in the place you want it to print on your shirt. (You could instead tape one of the acetates to your platen and use that.) You should really have registration marks on your design that are in the same place on every screen. You do that when you print out your acetates. They will also now be on your platen. You need to now carefully align all your screens to the one you taped to the one platen and tighten up the screws. Be careful when tightening up the screws as it could move.
Anyway - make a print of your design and tape it to your platen in the place you want it to print on your shirt. (You could instead tape one of the acetates to your platen and use that.) You should really have registration marks on your design that are in the same place on every screen. You do that when you print out your acetates. They will also now be on your platen. You need to now carefully align all your screens to the one you taped to the one platen and tighten up the screws. Be careful when tightening up the screws as it could move.