I always send a proposal to my customers – even my very good friends – via email. It has a description of the order, price/tax/total and delivery date and location. I tell them that once they confirm the order via email (so I have a record) I will put them in my baking schedule. I also remind them to look carefully at spelling of names, colors, etc., so that no mistakes are made. They very rarely catch errors, but at least it makes them double-check and THINK.
I’d send a summary to this person and have her reconfirm, ‘just so you can verify with all the changes that have been made.’ Good luck!