To build a habit that will stick, make sure that you start small and do it every single day (preferably at the same time, and in the same environment). Do not wait for motivation to do whatever it is that you’re trying to do (work out, read more, etc). If you only do it when you feel like doing it, chances are that it won’t get done.
Associate your new habits with pleasure. When it starts hurting, then stop. But keep coming back to the habit the next day, doing at least the minimum of what you set out to do.
You can also “stack” your habits (from James Clear) where you are adding the new habit to an existing (similar) habit that you have in place. Since you already are doing the existing habit, it won’t be as hard for you to add a new one because you don’t need another trigger.