With the boards surfaced and cut, we can begin to work on the side panels. Use the smaller board for the side panels. You can choose any shape that will rigidly hold two dowels in a parallel orientation away from a wall. Both side panels, at this point, are identical, so you don't have to worry about making two right or left hands just yet. Make sure that you have enough wood for the pattern you select. You can flip the pattern over for one of the side panels to fit on the board you have.

We will be laying out grooves for the dowels in the following step, but their location comes into play now when you are finalizing the side panels. The wider the space between the dowels the more room you have for the magazines, but an extremely wide pouch fails to neatly hold the magazines. Anywhere between 3" (75mm) and 6" (150mm) is suitable. We let the wood we had dictate the width. After accounting for the back panel to protrude through the side panels, we were able to have a dowel center to center distance of 3 1/2" (9cm) which holds a suitable number of magazines. Choose a shape that satisfies you. Also note, that the two dowels should be parallel but they do not have to be at the same height. Our front dowel is slightly lower than the rear one so that it is a little easier to access the magazines. Raising the front dowel higher than the rear, on the other hand, would be counterproductive.

Mark one of the patterns that you will be using and confirm that you have enough room to cut an identical pattern with the remaining wood. Cut this pattern with a bandsaw or a jigsaw and finalize the shape with a disc sander and/or an oscillating spindle sander (or drum sanding attachment for your drill press) if you have interior curves. Once you have one of the panels finalized, you can trace the shape you just created to make the second panel.