You can carry the tent poles of a freestanding tent. You can use these with a military poncho to make a shelter because the poncho has grommets already.

For a hot desert (not all deserts are hot!) you really need two layers for your shade shelter to drop the temperature significantly. If you have tow layers with a good space between them which allows the air to move freely the temperature under the shelter will be much lower than just one layer. I would use the heat sheet, silver side up, on top.

Even one layer is good, especially something as reflective as a heat sheet, if it is high enough over your head. A low shelter will build up hit quickly.

A space blanket with grommets will be easier to set up than a heat sheet. Having the hiking poles will help, but you do need a bit of cordage and either stakes or rocks to anchor it.

If you are going to a place that is flat you will need a freestanding shelter. I actually do like umbrellas for these areas. You can carry your shade with you and they are airy.