Tick anything you already have, in any order. Quests unlock once this is done.
Thicker than a yoga mat, because a lot of this happens on your spine and tailbone. A thin mat on a hard floor is the main reason people say it hurts.
2 things left above. Quests are real things you go and do, so they only make sense once you have what you need.
First one waiting: Follow a beginner mat routine