I do two things:
- Limit lessons based on number of upcoming reviews in forecast for the next couple days (and try to factor in any non-WK plans I have, like if I know I have a vacation plan coming up and won’t keep up with reviews, I try to plan ahead).
- Since I’m REALLY bad at remembering new kanji, but actually pretty good with vocabulary, I also use the WaniKani Lesson Filter userscript to start learning some vocab unlocked ahead of the next kanji. I also use this just after a level up to do the newly unlocked kanji ahead of the vocab from the last level.
So I usually do, say, 5 new kanji, then 10 vocab one day, then depending on if I’m doing well or not on those and how big my backlog of reviews is (which I gauge by the upcoming forecast), I’ll either add more lessons the next day or skip a day and do more lessons the day after.
Definitely in this for the long haul and I already burnt out once and had to come back from a break to thousands of reviews, so trying to keep it slow and steady.