To create a new lead simply click on the New lead button at the top of your home page, or in the header bar of any other page.
Adding leads is a key part of the process of using no crm.io. You can fill a lead with any kind of information but try to keep the contact info at the very beginning of it so you can see it all the times.
When creating a lead, the fields that appear are those that you have predefined in the Admin section of your account. It's important that you define them correctly!
Moreover, you will be able to define right away the amount, probability, client folder, star it (if it's a very important lead), attach a document and even add an estimated closing date if you have the Expert Edition.