Making a flex sensor was easier than I anticipated. I used resistance fabric, conductive fabric, thread and felt. I cut these fabrics and ironed on the conductive fabric to the felt.
I sandwitched the fabrics in the order below and stitched on one side of the fabric close with a whip stitch.
I used the multimeter to check if my flex sensor was working.
Once my flex sensor worked I hooked it up to an Arduino and used it’s output values to make an LED fade.
My sensor output was 650 when it was low(still) and 1020 when it was high (bent/force applied)