Do you have any advice for selling food products from home over the internet?

I live in Washington and my mother is wondering about how to go about selling food products from home. She has a food liscense, but she has to get it updated. For example, if she was to sell her pepper jelly on a website that allows the sale of homemade food products, how would she go about it? What would she need to have liscence-wise, kitchen-wise? Stories of personal experience are greatly appreciated.