You could start with something as simple as a piece of the person – a hair, maybe, or a letter they’ve touched. This connection acts like a homing signal for your spell, ensuring it finds its mark no matter the miles that lie between you.
Then there’s the idea of creating a small figure, a representation of your target, aka a poppet. You bind this figure to the person, making whatever you do to it happen to them.
The below is in A Sacred Space
https://forum.spells8.com/t/poppet-dolls/45197
Visualisation is also a powerful tool. You’d close your eyes, picture your target, and wrap them in the spell’s energy.
You could also draw a symbol that’s uniquely theirs, a sigil that ties your spell directly to them.