My biggest problem is writing/presenting efficiently. Usually I spend several hours on a single paragraph or beamer slide. Today I spend all my time preparing my defense presentation (besides social media), but only made drafts for two slides.
And my advisor is also very busy. He says he will write the introduction for a paper and then finds no time to finish it
The making of slides (or sentences in a paper) gets easier with practice. The advisor or collaborator or you yourself being too busy is, unfortunately, not something that gets better with time. The most important thing is learning to say "no" to new responsibilities without becoming an irresponsible member of whatever organization (university, research lab, etc) you find yourself in. It's a balancing act.
And my advisor is also very busy. He says he will write the introduction for a paper and then finds no time to finish it