Ever wish you had someone to put you in your gym clothes? Carry you to the gym? Or even do the workout for you?! Same. What we refer to as 'motivation' is usually what we think we need. What if I was to tell you, you're wrong? What you really need, is habit.
Let's say you're working towards a goal. What does the end picture look like? What does that person do every day? What do they eat? What do they wear? How do they act? How do the feel? Perhaps all of those things put together seem a million miles away from where you are now.
Pick one thing that will get you closer to that person. Perhaps it's packing your gym kit the night before to take with you. Maybe it's planning your meals for the week. Once you've nailed that down consistently, move on to the next bit.
None of this is quick or easy, but what it does mean, is change. Rely less on motivation, more on habit changes and bamn! Who even are you now?!