The biggest lesson from Team Sootch is use your head, then your gear!
T-shirts are readily available in most survival conditions. Clothing is usually commonly available if you look around The uses for the shirts are very simple: from kindling to cleaning patches, you have many uses for a shirt.
Basic filtration is also a good use for the shirts. Filtering for air and water, the shirts keeps the smaller particles out of your nose and throat.
Simple first aid uses are also an important use. Stop bleeding and cover open wounds with a clean shirt to keep dirt from entering a cut. Covering wounds as fast as possible prevents infection.
Keep an open mind if you're stuck. The gear around you will always be of good use. Stay safe and stay motivated.