Keeping a journal is a great way to relax or contemplate. It can be used to write about your days, thoughts, ideas, and track goals. Some journals are only writing, but you can also attach photographs, use stickers, or draw. It is also great way to share memories with friends and family. Or you could create a journal that is for your eyes only.
You can use a plain notebook from the grocery store, small journals, diaries, sketchbooks, or even planners. Whatever fits your budget and interests can be used.
If you're not a pen and paper fan there are also apps that allow for more creativity and playfulness then Word or Google doc.
-Updated the "Finding Inspiration", "The Right Journal For You", and "Suggested Reading".