Habit

A settled or regular tendency or practice, especially one that is hard to give up.

How to create a habit?

Place and time .

You need to fix a specific place and specific time to do that work.

For example,

You want to workout in your home

1)fix a place 

2)choose the time where you can freely do it

Without any interference.

After a few days you'll automatically wake up and do the work without your consious mind working on it.