I draw mine on a CAD program and print them out, I draw and print in FINE line.
Also when printing go to --printer setup, properties, and click on (General Everyday Printing) to get FULL SCALE
You can also draw 2 lines 10" apart and measure them after printing.
I cut 2 pieces of 3/4" plywood
I cut down the center where the first stripes will be and tap it down on one side.
Now I can fold them back and use some double sided tape to hold them in place.
The double sided tape is used for Metal buildings to hold the Insulation on until the sheet metal is screw on.
Just google Metal building double sided tape and you should get it, maybe Amazon is where I got it
I cut close to the line and now I'm going to sand until the line is gone
The paper want's to roll up when sanding and you cant see the line, so I roll it back down and sand it with 120 grit going straight down down down down down with my thumb backing the sand paper to cut it off, I keep sanding and doing this until I like the way it looks.
I cut some lams for the stripe in the form and grind the 2 lams to .0625 for a total of 1/8" and clamp the templates together.
One 1/8" stripe may be hard to bend into the shape.