Well the most basic thing is the most basic thing.
Clean your desk.
If you are not working, or not working from a desk, clean something. A side table. A small space.
That is the seed.
You are creating a nice spot and a nice place to start.
Each day, improve one thing about your environment. The rules: none really, but it can be small. Put away a paperclip. It can be medium, put up a shelf. It can be large, donate most of your stuff. But improve one thing about the environment you are in.
What can you expect? Most of the days, it will be little stuff, putting away socks you left out the night before. Lining up notebooks so the corners are square. Seemingly inconsequential things. But some of the days will be huge. Finally fixing the window so you can have bright sunlight. Moving all the stuff around so that you can easily work out and it is harder for you to do things you do not want to do.
Everything you change and improve is an improvement.
Eventually you will realize that there is finding contentment within yourself as well.