I will assume you will end up with straps with no loops. I am fairly certain you can wrap around the tree twice and then put both ends of the strap in the marlin spike hitch. Doing it this way you dont have to sew and you dont have to learn any new knots. I dont do this. I went the AHE route and bought straps with loops. Not so sure you could make this work if you only wrap the tree once. Unless you were directly over a branch I dont think you could keep it from slipping with only one wrap. Another no sew option is to take the staps to a shoe repair shop and let them sew in the loops. By no sew I meant that you are not sewing.
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