How do you leave your mark on someone, something for them to remember you by?

Usually with a sharp knife

Permanent marker.

It could be in a random act of kindness or offering assistance to someone having car trouble. There are so many ways you can have a positive impact on another person's life. You could listen. Run errands. Be a good friend or neighbor.

Tminus6453 · M

I leave my scent

FeralMindset · M

If you have to try you won't be successful. Those kinds of things take time.

Picklebobble · 56-60, M

Write them a letter.
Something they can keep their whole lives.
Might have to edit it several times before you get to say exactly what you want to say.
Thank goodness for MS Office though, right ?
Once you have what you want to say. How you want to say it.
Physically write it down.
Handwritten letters are a nice rarity these days.