I would say very carefully, put everything in writing. Hours, pay, review for a raise (every 6-12 months), being on time (what happens if your not), calling in sick, or late (who they call, emergency #'s).
You may not need to offer benefits, if you don't have fulltime people, but make clear any benefits that you do offer, such as a product discount, paid vacation days, ect. You will need a very clear JOB DESCRIPTION, what is common sense for me & you may not be to someone else. How do you want your store to look at all times? is she to clean, answer the phone, how exactly do you want your customers to be helped, how much product knowledge does she need, how will she get it, bathrooms (when to check them ect..) What is she to do if things are slow (sit on her butt?, cleaning chores?, redo displays?) When are her breaks? are they paid? How do you envision her ability to work w/ baby? What will happen if she can't get her tasks acclompished b/c of baby?
How will you handle the cash box (people steal, even the ones you know and trust) if you have a good cash box system you can prevent problems, and you won't have to change things later, which is hard on people. Those are just my first thoughts, the more clear you can be about every little detail the less room there is for misunderstanding later. Good luck!!
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