The reward system is a very popular and effective way of motivating people and animals too.
You can apply this to yourself if you are aiming to build a new habit.
It can be as simple as your favorite food to an extravagant gadget or workstation. Whatever it maybe, be sure to make your reward very satisfying. This will make your brain anticipate satisfaction every time you do your habit.
On the other hand, if you are always not following thru your habits, maybe because you are not rewarding yourself satisfyingly.
To make your body motivated to do a task, remember to reward yourself, you deserve it.