I haven't used self adhesive velcro on clothing, but have used it for other things. I don't imagine the glue would stick to well on clothes. I would suggest using some sort of glue, but I don't know what sticks to Goretex.
Exactly what Beaker said. The best way you can convince people to give you work is to something to show them your capabilities. I can think of several people who got started that way. My original career was in medical research. I got involved in IT when we bought a new scintillation counter that came with an Apple II.
Previously, we had manually recorded results by copying them into a notebook from the teletype output. The Apple II came with no software or interface to the counter. Over a period of about 6 months I worked out how to interface it to the counter, record the results and do the stats on the computer.
I used this knowledge to move into IT, where I spent about 15 years. New technologies appear all the time. If you can get in early and prove you have some practical skills, you will always be able to find work.