Only advice that has ever worked for me is to set micro-goals for the start of tasks.
Like, stupidly easy goals. Got a paper to write? The goal is to open a new document and type 3 words. Need to go work out? Do 1 push up. Need to clean your room? Put one shirt in the laundry hamper, or take 1 dish to the sink.
That's it. Stupidly easy. Not feeling it after that? Cool, you already hit your goal. But momentum is a hell of a thing. The majority of the time, I'll just keep going, precisely because the micro-goals was so easy.
3 words done? Ok that took no time at all. Might as well finish the sentence, maybe even a whole paragraph.
1 push up? I'm already down on the floor, why not do another? Or 10?
I could grab just 1 shirt, or just 1 dish; but I could grab more at the same time. Might as well.
You don't need to trick your brain into doing the whole task, you just need to trick your brain into starting the task. Momentum will take care of the rest. And on the times that it doesn't? Well, again, that's fine. You met your goal already. You don't HAVE to keep going. That can be enough for now.
