From neuroscience perspective, it is the Anticipation of the task that releases dopamine, not the "Doing" of the task, hence the appeal of all the productivity porn.
And as a corollary, it could be the Anticipation of difficulty in tackling a daunting task that makes you avoid it, rather than the actual difficulty in tackling.
So, the best way to getting into the flow state and getting things done (pun intended) is to force yourself to just do it.
Minimizing friction has been the game-changer for me. I don't avoid easy-to-do things, I just do them. If I can pre-load getting rid of friction I do.
For example, a meal plan generator was an expense I justified because it grossly simplified meal-planning and shopping. Removing that bit of friction made me much more likely to stick to my plan to more healthily.
And as a corollary, it could be the Anticipation of difficulty in tackling a daunting task that makes you avoid it, rather than the actual difficulty in tackling.
So, the best way to getting into the flow state and getting things done (pun intended) is to force yourself to just do it.