I'll just speak from personal experience.
Having a lot of free time last year, I thought I could at least go through my endless folder of projects and brush it up, work on major stories and get the writing done.
But to be honest that all sounded like a lot of work. So it was boring, and nothing really got done. I needed to write, whether it was to add words to my wordcount or just to capture that feeling I had way back when.
(Interestingly enough this year I found a bunch of notebooks I had filled up page to page with stories. Even with what I know now, I still haven't that level of freedom and fun. )
In any case, after long weeks of a whole lot of nothing I suddenly decided to RP for the first time in my life.
I don't know jack squat about RPs even after being in this one for the better part of a year, but it was an amazing novel experience where 'art' is shared as simple communication. What people would painstakingly label as fanart or commissions was a simple share between people. I drew a heck of a lot for random ships, funny events and action scenes that had happened over the course of the RP.
There was no solemn 'I am drawing something' moment that made me procrastinate on the project. Between friends it was just a fun fulfilling experience. Rather than dread at the time needed to be spent on the drawings, it was an impatient anticipation to produce the drawings that drove me.
Later I even ended up saving endless dialogues and character moments, and wrote up an AU short story involving up to about 15 characters. Was it a great piece of literature? Nope, not at all. Was it fun as hell to write and a great learning experience? Hell. Yes.
I'm going to summarize all my points at the end so I'll jump into another personal experience. Writing MR stories. It's sort of the same thing with the RP, but still, I've got to mention that writing them gave me such a sense of freedom I remembered completely why 'being a writer' seemed so attractive for me. Other than the whole being rich and famous bit.
Spontaneous collaborations as well are great. I've had a few before, but I intend to get into more. In fact this very night I'll ask someone to joint write a story, just for fun. And I already did one with swearzy and Frono for our Anthology story.
So, in summary here are my tips.
1- RPs and fanfiction. I used to think that fanfiction/art was pretty cheap and easy to get into, but there's something so great and communal about working on these sorts of things. Just a protip: Mary/Gary Stus tend to piss off everyone. This also means that if you write for an RP be careful with making your character the MC. It's hard but practical.
2- Collaborations. These are never easy. But they are undeniably fun when they work out well. And the more people the better.
3- Bigger does not mean more accomplished and/or better and/or fun
This last point I didn't explicitly meantion, but just because you only have an idea that spans 300 words does not mean it isn't still a good piece of writing that's worth reading.
My procrastination sometimes comes from the idea that I want ALL my major projects to be novels of at least 50,000 words in length.
Be willing to write a small moment as your writing for the day. Heck, for the week even.
This was so true for my RP times. I'd just type a quick 'brb' and draw something real quick and post it. Is the quality god-like? Heck no. Is it fun as hell? Heck yes.
My two cents.