correct me if im wrong, but there are a lot of factors to that scenario. for example, im a newbie to screen printing. i did my shirt and it turned out jus like yours, the ink passing thru the shirt. after "analysing" and understanding the whole process, i found out
1. i was pushing too much ink
2. i need a more thicker ink
3. or i need a finer mesh.
so wat i did to rectify it was, make sure u have enough ink and do 1 pass on the shirt without flooding. i know it may sound weird but it works!! for me at least. no more bleeding around the design nor passing thru the garment. then do a back pass to prepare for the other shirt.
hope that helps a little