I figured out something very helpful recently. I was having some trouble keeping the pins in place along the long seams where I had to topstitch. I remembered something I saw my girlfriends grandma do with a quilt. She had used a single strand of thread and using a very very long stich tacked the material together before doing the real sewing. After sewing the single strands can then be pulled out. That method worked great for keeping the material tucked under it self to make the seam lay right. Tonight I will be doing that with the last seam between the floor and the tent side and then the tent will start going 3D finally smile