Cut the ends of the pixels and remove them from their silicone case

Measure out some strips of paper down to the size of some various strips of pixels

Pin them to the jacket to see what would work best.

I decided on 8 strips for each side, ranging from 4-11 pixels in length.

Since the copper pads on 144 pixels/meter strips are on the tiny side, it's easiest to cut out and lose a pixel between each strip. 

The Larson Scanner Shades guide illustrates this in the wiring step as well. 

Cut pixel strips to desired lengths.

Keep an eye on the half way mark on a meter of pixels. Since the distance between pixels isn't equal, the strips can be desoldered or cut around. 

Cut silicone pixel covers slightly larger by measuring up a pixel length. For example, I cut a silicone cover to match the 10 pixel strip and used it for a strip of 9 pixels.