I'm Thinking About Making an Employee of My a Partner

i'm considering making an employee of my a partner. Can you just help me walk through this little bit? I don't like that idea ever. How do i know if it's the right move, and how do i navigate this conversation properly? Do how do i talk properly about percentages as theyre by in? "I've had employees that have been with me for a ten-year period who somehow get into a situation and it changes their whole life"