I have love for pockets... Everything is easier with a pocket.
Also, once upon a time I made, and have a pattern for a square bag.
It's a 13" square, you cut 2 one is the top of the bag and one is the bottom... not front and back, but top and bottom...
The top is cut with an X that is the opening.
The X is cut 3x3
You make a facing for the X out of a square fabric 4x4
Sew the facing to the top right sides together with a 1/8" seam allowance
Turn the facing inside, in the same manner you would a self faced button hole
The top and bottom squares raw edges are pulled to make a self fringe.
Sew the top and bottom together with wrong sides together
All the corners on the top and bottoms are sewn together diagonally so that they make 2-3" triangles.