Oversized T Shirt To Comfy Yoga Pants

Emily!
I'm glad you like them!
I would suggest looking at the first part of this tut, where I got the idea from: http://www.cutoutandkeep.net/projects/oversized_t_shirt_to_comfy_yoga_pants
But if you want to do the rolled top, take a shirt that's tight around your waist and cut a straight line across just below the sleeves. (You can also use a bigger shirt if yo cut off the arms and sew up one side to make it tighter.) Slip the shirt over the top of the pants good side up and sew the rough edges together. Then, all you need to do is scrunch up the waist band, and you're set!
Feel free to ask more questions, I'm glad you're excited to go to the thrift store!

Okay I really want to do this; can you explain in a little more detail for those of us who haven't had much coffee today? I lovvve them and now I have a reason to go to Goodwill

Thanks!
Yes, I just winged it. I cut up the middle and cut the sleeves off. Then I sewed the arm bits together to make the crotch. I sewed together what had been the middles to make the outside pants seam. It probably only worked because the blue fabric was extremely stretchy.

Love em...did you use a pattern or just sorta winged it?