I don't have pictures yet, so bear with me. Edit- Pictures!
 
Construction time- 5 minutes (not even)
Materials- Duct tape, string, hole punch / puncture device, dirt / sand
 
Take a piece of duct tape, say 5-6ish inches long, and lay it on a flat surface. Take another piece of duct tape of the same length and stick it to the first piece on the edge, so the two piece make half a square. Now, bring the two separate ends together at the other end as if they were going to make half a square. You now (hopefully, have a pouch!). Cover the stick side of the tape with dirt / sand/ substance that will remove the stickiness, so the tape won't stick to itself, etc, running your pouch. At this point, fold the corners down inside a bit, and take a hole punch / knife / puncture device to make a hole at either end where the two pieces come together (or at your folded down bit). Thread some cord of any type through the holes, tie one end outside the hole, and make whatever release cord and finger loop cord ya want.
 

I think I'll use this sling for my hobby idea, because it really is quite easy to make, and it'll get em started.
 
If could, please try this and test it now, and give feedback, I think it works, but more advice from others slingers is wonderful!

for speed i prefer just laying two pieces of tape sticky side to sticky side and attaching cords on aussie pouch style, but with a duct tape wrap rather than whipping.
 
for actual long term use i like to cut out two diamonds/kites from duct tape cloth (2-1/4in widex4in long) tape the two bottoms together to make a cupped pouch, add extra duct tape and the tips and punch holes. attach cords by threading a cord through, bending and wrapping tight with duct tape.  
 
not using my computer so i can't post pictures.

Duct tape slings; easily quickly made, cheap, they work just fine...
But they are so d....d UGLY!

Quote from kuggur slingdog on Jul 1^st, 2011, 5:01pm:

i actually make ones that are not ugly, they actually are very nice.