Tools
Prick_Wheel
Prick Wheel

Draw_stitch_path

Prickwheel_on_bag

Prick_holes

What you must achieve here is a line of stitches that is evenly spaced, and following a very smooth curve about 3/8" from the edge of the bag. I find that a spacing of three stitches to the inch is ideal.
 
Prick Wheel. Certainly for a beginner, I would recommend the use of a prick wheel to mark out the path for the stitches. In the early stages, I would also recommend lightly pencilling out the stitchpath before using the prickwheel. It is very important that the stitches are evenly spaced and even more important that they follow a perfectly smooth path. One stitch a little out of line with the others can set up stresses in the bag during use that will eventually cause a weakness in that area. If you don't have access to a prick wheel, you can mark out the stitch positions for the holes, (5/16" apart), just as well with a ruler. It just takes more time.

 
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