Securing your website is another important consideration. One of the last things you want is sensitive information being taken from you or your users. Things like passwords to messaging, account information wherever there is money involved, and pictures and content intended for limited audiences are things you have to secure. There are a lot of people who may want to compromise your security for access to these things.
Preparing yourself for disaster is probably the least fun thing to do an the most important thing you wish you’d done if a disaster strikes.