Fuck Motivation. It is a fickle and unreliable little shit, and it is not worth your time. 

Better to cultivate discipline than to rely on motivation. Force yourself to do the things. Force yourself to get out of bed and practice. Force yourself to work. 

Motivation is fleeting and it is easy to rely on because it requires no concentrated effort to get. Motivation comes to you, you don’t even have to chase it. 

Discipline is reliable, motivation is fleeting. The question is not how to keep yourself motivated, but to how to train yourself to work without it.