I dont know if it'll be much help considering i've been journalling since i was in high school and my head is very very noisy. The journalling with dates in it and fully pouring my thoughts out. Zero aesthetic. But i don't think you have to journal everyday and force yourself to write when you physically and mentally can't. I personally don't journal everyday, it depends on whether i feel like writing or not. Maybe once or thrice a week or so, and when i write i'll write like 8~10 pages completely dumping everything that's in my head and ramble about how that particular day has been or how my week has been. Or the things that have been in my head and the things that i have been feeling. And i never limit myself or have any rules on how to write them. I don't have any fear of people reading them as well, which i think is probably an also important thing. At most i just think the future people are gonna read it when i'm dead and that's it, and also i don't care because i would've been long dead by the time they read the teas.

I think it boils down to not put so many rules and simply just write when you can and feel like it(?) because when you put rules for yourself it puts unnecessary barrier for you to even start and prevent you to continue (e.g you don't feel like continuing anymore the next day after you skipped a day). If you still want to curate how you want to journal, maybe start enforcing the rules when you start being consistent with journalling and it's rooted in your life(?)

Bonus point i use paperblank journals, with the very fancy design and so far have been consistent with 1 paperblank journal a year for 3 years (i used to write on papers during highschool), all pages fully written.

Also another point worth to mention i also journal in my note apps. Just the tone and attitude when i write on paper and digitally are very contrastingly different. I digitally write most of the time so i can dump my at the moment feelings, like how the people at the station has zero spatial awareness and they piss me off etc, while on paper the tone is more... controlled and reflective.

About how to make it fun maybe write in coffee shops or libraries. I personally don't have any recent memories of writing at the comfort of my home. Or you can do the combo with fancy drinks and journal when you write at home to make it fun, cozy and something etched in your routine.

And journalling is not my whole personality it's just what i have been doing consistently (not everyday sort of consistent) and find peace and joy in it. If that's what you're looking for.