If an unknown word includes a new kanji, I just learn the reading and meaning for that word and move on. I don’t really worry about what other readings that specific kanji can come with. If I need to know it, I’ll encounter it in the future.
If I was to study specific kanji outside of wanikani though, I would probably look up the kanji in Jisho, click the “words containing 例” button and choose some common words from the list to add to an anki deck or something. If both the kun and on readings are frequently used, select words where both readings are used.
This is a poor example due to probably “rare kanji” but you get the idea.