how to stay motivated with moving and/or non-existent deadlines?

in america, deadlines are there and they're decently strict, particularly for school. meanwhile, in the great land of cyprus, it is a lot more lax. most of my classes don't have strict deadlines for turning in homework (as profs don't grade it regardless). and then my one class with a strict deadline (data structures), often moves the deadline to a week or more later. and quite frankly, i am the kind of guy who doesn't do anything until necessary (and believe me, i am trying to correct that). thus, i have the issue wherein i don't do work for multiple weeks at a time, and then suddenly i do all of it at once. not a very healthy way of work, certainly.

the answer to the question posed in the title? lmao fuck if i know goodbye