Ideas but the instructions on how to create the shelters are lacking detail. Experiment. Most tarps I see have round metal grommets so have plenty of twine or rope or whatever you have. Many things can be used as pegs. Your circumstances may not allow pegs so maybe your weight may be what holds the tarp down.
You may need to be mobile; staying a day or two then moving on to a new spot so that the cops do not mess with you. If lucky you may have a long-term spot. Try to disguise the site so that it is unseen unless a walker runs into it. In an isolated spot walkers may be rare or non-existent. Camouflage your site. Vegetation is useful but be prepared for winter when vegetation thins out. Adapt to situations and circumstances.
Consider the “lay of the land.” Do not place your tent where rain water will collect and place you in a puddle. A ground cloth using a tarp is a good idea.