Nancylou

I made and quilted a pillow cover for someone. I spent about 6 hours on it. What should I charge of the the time spent quilting and assembling the cover. Never done this before for payment. Do I charge by the hour? I spent about $30 on the materials.I don't know the person . I made a pillow for my daughters puppy and the breader where she got him from liked it and wanted one. Any suggestions you have on figuring this would be helpful.