It's important in any survival scenario to make use of anything you discover or already have with you. You can often discover useful components eventually forgotten by others. Old climbing rope or some ripped plastic sheets can be of great use in the nature. You should always collect whatever you have and keep it at your disposal. Products like ponchos, nylon sleeping bags or parachutes can provide for shelter.
If you have a poncho or any type of plastic sheet, you can develop several different kinds of shelters. What you want to do is simulate the appearance of outdoor tents. For a basic shelter, all you need to do is get under the item you have. If you have some rope, you can tie it between four trees to form a cover.
You can style an outdoor tent refuge by operating line down the middle of the plastic sheet between two trees, then staking the edges into the earth with sharp sticks to make an A-frame. Another simple shelter can be made by attaching two edges of the plastic sheet to plants. The other end slants diagonally to the earth and can be properly secured with sharp sticks or heavy stones.
if you don't have any rope, you can always build a shelter from branches. First stick 2 long branches about a foot to the ground in a triangle position for the entrance make 4-5 more triangle position from branches to support the main branch that will be the ceiling of the shelter. You should find vine or thin green branches to lash together all the support points so the shelter will be strong and sturdy, put the poncho/plastic sheet over the frame you build and stake it to the ground. The main pole (the ceiling) has to be on a descending slope so the water will slide down and won’t get into the shelter, also make sure you have enough room inside so make the triangle shaped branches big.