Thanks for the response.
Are you describing the process for the back or side pocket? I'm only confused about the pattern for the side pockets as I can't figure out how to make darts or pleats along the curved seam without negatively effecting the alignment of the seam.
An alternative might be to not use a pattern and just use a lot of material and sew along the curve making pleats as I go until I get to the bottom where the shoulder and hip straps are attached, then sewing the side straight up to the top of the pocket. I could then trim excess material, but this way would probably leave more room for error?
At this rate, I might just end up putting traditional square bottomed side pockets on, although they would have to be higher up on the pack than desired to avoid the curve. Stupid curve.
EDIT--Actually, is it even necessary to make pleats or darts along the curved seam? Can I just make 1 or 2 larger pleats at the corner by the pack strap connection?