Using a kanji dictionary
How to find an unknown kanji by reading, meaning, and usage
Check the reading of the whole word and its role in context, not just a single gloss, so the lookup helps with future reading.
Key idea
Search the character itself when you can copy it, or use hiragana when you only know the sound. Try every clue you already have.
How to use it
On and kun patterns have exceptions. Check the whole word including surrounding kana and compare examples close to your context.
Next step
After looking it up, say one example word aloud, inspect the stroke order if needed, and reread the original sentence.