You need three things basically:
A trenching tool or similar;
An ice cream container or similar; and
A sheet of plastic about a metre on each side.
- Scoop out a shallow depression in the ground.
- Place a reasonable quantity of water bearing foliage into this depression.
- Place container in the centre of the depression.
- Place plastic over the top, holding each corner in place with either a convenient rock, or a few handfuls of soil, if rocks are scarce ...
- Place any convenient weight object in the middle of the plastic above the container underneath. This causes the condensate to run down the underneath of the plastic sheet into the container ...
- The hotter the day, the more the water collected. Don't use it for having a shower .
Hope this is complete ... It does work.
BTW, I have done the glove box letter you suggested for both our cars.