For desert survival, make a solar still

A solar still collects water out of the atmosphere. You require a large sheet of plastic, some rocks and a container to catch the water in. Dig a whole in the ground, spread the sheet of plastic over the hole, anchor it on the sides with rocks. Then make a depression in the middle of the large sheet of plastic. Underneath this depression put a container to catch the water.

Search on google for a diagram.

 

Have you actually done this?
I have!
It is mostly Bollocks! as you gain a net minus result!
The water and effort expended to set it up is more than you get in return!
The only really water positive collector is the plastic bag over a tree branch thing!, it is quick and easy to set up and you can set up multiples on the same tree!
One person can set up dozens of bags and actually accumulate water in excess of needs!

 

I agree about the net minus result, at least in the short term as you'll sweat more digging than you'll collect! The plastic bag method - or transpiration method as I've seen it described, since that's what it's based on, is very effective. Be sure the bag is tied on as airtight as possible, the more leaves inside the bag the better, you'll need to strain the water collected and, finally, move the bags regularly. You don;t want to kill your water source! Also, be sure not to use a poisonous plant.