With upholstery fabric you don't need interfacing, just a lining.
And the lining can be great way to use those fabrics you have that you wonder why you got in the first place!
I like to put pockets inside near the top, sometimes one larger than the other, for phone, keys, etc.
Be sure to back stitch at least an inch at beginning and end when attaching the pockets.
If using the webbing for handles be sure to melt the ends so they don't fray out!