For T-1 skip the towel off. The wind on the bike ride will dry you fast enough .

I setup my transition area on a towel folded in half. On the back half I put my running shoes.

On the front half I stack the following items: bike shoes, then socks, helmet, sun glasses, jersey. When I arrive at the transition area I sit down, towel off my feet just enough to get the sand off. I then put on jersey, sun glasses, helmet, socks, bike shoes and then I'm off.

Generally speaking you shouldn't worry about your stuff in the transition area. I have never heard of anything coming up missing in any of the triathlons I've done.