A what NOT to do:
I was doing some paper-based piecing - and I thought I would be SO smart and sewed about an eighth of an inch from the edge of the foundation so nothing would come apart.
I used recycled copier paper. Which is kind of hard to pry off, also.
And then I sewed my blocks together.
Things were great until I tried to get the paper off. So - if you feel compelled to sew around the edges, either hand baste or machine baste - and then remove the stitching before trying to get the paper off.