How about your outdoor clothing? What do you wear?
I prefer lightweight trekking gear. I like to wear shorts and a t-shirt in the summer. A t-shirt for me is much better than a tank top because oftentimes your pack digs into your shoulders and can be quite painful with the straps of a tank top. I love using merino wool products, especially for longer treks. They are lightweight, moisture wicking and dry really quickly. They are also thermal regulating and repel odors… a great idea for long treks where you opt out of bringing multiple changes of clothes.
How about food and drink: what should you take with you, what can you buy/get on your trip? (How) Do you cook?
This really depends on where you are going. For example in Nepal, we hardly had to bring food because each place we stayed in tea houses and the price of lodging often included your meal as well.
For trail running in remote locations, a stove is part of the essential gear you should be bringing. There are lots of different brands of dehydrated meals and they usually taste really good. For most of them, the only prep needed is boiling water and adding it to the package to let it cook while you soak in the views.