Honestly? You have to make it a habit. Motivation will not always be there. In fact, it seldomly will.

No motivation? -> Just do it anyway.

Do a bit of googling on how to build habits. There are many books on the subject: Atomic habits, tiny habits, the power of habits.. You don't have to read a book, just any 5 min video will work just the same, or a blog post or similar.

EDIT: Just noticed that this post is 2 years old..