Some days/week I get into a spiral of a sad/unmotivated state of mind. How do I get back to normal? Preparations? Checklists? Ideoms to remember?

Make it something that you rly like. Corelate what you do with a lovely activity or sth like this. Put stickers, posters, sticky notes in your room, in your house, every where, make your environment as suitable as possible for your activities. So you can get in touch with all the tasks that you have to do throughout the day.