Help with creating a cross stitch pattern?

I want to create a cross stitch pattern of a picture i have. i downloaded the graph paper but now I’m stumped as to how to transfer it onto the graph so that it still looks like the pic. any help or ideas? i would download a program to help me but i have a mac laptop and i can’t seem to find a good program that works on my OS

You could just print the picture on graph paper.

Hand Sewing : How to Design a Cross Stitch