When you're practicing, keep a pencil handy. It's an underestimated tool for supercharging your practice effectiveness.
Use it to bracket off tricky sections for untangling.
Use it to remind yourself where to look or think when you arrive at certain places.
Use it to circle pesky accidentals that won't stick on their own.
Use it to write how different passages of the music make you feel.
The possibilities are endless. But only if you have a pencil handy.
Just don't write letter names in the music. Because that's so useless, it should be illegal.