Describe precisely what will happen after placing an order. The customer needs to be aware of the time that the seller requires to process an order (from the moment a product is placed in the cart, to the actual delivery).
In case of online payment each product is send short after transaction.
Parcels are delivered by couriers. Delivery time depends on the chosen company, kind of order, recipient's address. Usually it takes 2 business days.
In case of money transfer, delivery time can be longer, because the money has to be booked to the account.
Inform your clients about the way they will be notified about their order. Explain the meaning of different statuses (for example: 'accepted for realization', 'awaiting delivery'). Encourage your clients to log into their accounts and checking e-mail boxes. Configure and check by yourself the template of e-mail send by the shop.