I met a lady on line who wanted a baby birth announcement finished. She provided all the materials.
When I sent it back to her completed, she asked how much I wanted. I told her to send me what she felt my work was worth. She sent me $150. I am almost finished with a second birth announcement for her. She obviously values handwork.

Did you keep track of how many hours you worked on this project?

Not normally. I have some things I stitched and was wondering if I tried to sell them what should I ask for them. They are just small patterns.

Bye for now

PS someone said to just charge 1 or 2 cents for each stitch

At one time, I was cross-stitching small patterns on sweatshirts. I didn't know what to charge either but I thought that those who don't do cross-stitch didn't have a clue how much time was involved. I charged the price of the sweatshirt plus minimum wage for the time spent in stitching.

You can do it as Senior Stitcher says, with cost for materials and add your labor for wages by the hour. You have to set this, as nobody has a standard wage for cross stitch. Or, you can use the old system of a penny or two per stitch. If you figure it out both ways, then see what looks best for you.
Discuss your rate before you begin with each customer. Be surd that they acknowledge your pay in writing. Don't disappoint someone by not finishing, az the word spreads.