Having a user friendly site that allows your customers to intuitively find their way around your site is imperative. If it’s not easy for people to sign up/buy or whatever your want them to do, then they will simply leave. People are getting more and more impatient and its vital you don’t waste their time with unnecessary fluff. If you are asking someone to sign up for a mailing list don’t make the form 15 questions long. Get their name and email address and worry about the rest later. If sites have long loading times, intros or are just hard to navigate people will simply go to the next site and give them their money instead.

Usability Tip:

The cheapest way to do user testing on your site, is simply to ask your friends to use it.
Don’t give them any training and get them to pretend that they are a potential customer.
If you can watch them do it, you will gain even more insight into how people will use your website, and see how many clicks it takes them to get to your call to actions.
If you do watch them, make sure you don’t give them any help, as people coming to your website won’t have you sitting next to them coaching them through it.