Read the Danish version here: Den bedste kundeservice er uundværlig i din webshop!
I do a lot of online shopping, which I have done in many years. It has given me a good understanding for what good customer service is.
Make it as easy for the customer to reach customer service. Place contact information, contact box, chats and the like, where the customer looks. I really hate the web shops where you have to click a number of times just to find their mail. If it is not on the site I am on, I always get so annoyed that I leave the website. The contact information should at least be in the bottom frame and as a link in the header.
Is it a product that is very popular and you have not been fast enough to order a new batch, it is a good idea to let the product be active and write “Out of stock, available again in 14 days.”
It is incredibly important that your stock system is up-to-date with your inventory. If it says on the product site that the product is in stock, your customer expects to receive it within a few days.
Many customers also experience that they are putting products in their baskets, but there are no shipping costs showing. The thing is that your customer automatically will think that the shipping is free. She will get to the payment site and there she will see that she has to pay 50 DKK extra for shipping. Guess what she does.