On Amy's videos she shows seaming, but they are both on stockinette. I'm making a felted bag and after felting a sample decided it wouldn't make any difference if I did garter instead. I'm also slipping the first stitch so my edges look great, but now I wonder after reading past posts if that is a big mistake.

I'm about 20 rows in now. How can I seam slipped edges on garter stitch without making them super bulky?