Most account details can be found by clicking Sign In in the top right, from here you can Login, Sign Up or Set a new (forgotten) password.
Ticking Remember Me will save a cookie in your browser (so that you can be automatically logged in)
Once logged in: You can change your account details by clicking on your name, signing out is done via that link and Character list will populate all your characters in the browser.
If you have none, click Create New.
Creating a new Character with a name like "testDave" or "testMageBuild" will allow you to have multiple characters with the same name and will not be taken, then rename them into an IC name. Anything without test prefix will be compared to other names and if must be unique.
Element, Race and Wheels are all populated automatically for you so that you can only choose the options you should be able to. Please be aware, it may take a few seconds for it to update the results.
A newly created character will enable you to edit the details or delete.
In the Edit, you can Lock Character, this will allow you to start spending AP.
Back on the main character list, you will be able to "Buy Skills" and "View Skills".
After purchasing the skills you are allowed to buy, (if you can't buy it, you can't see the buy option) you can click on View Skills to view and then refund any skills you no longer want.
Selecting the Free Skill option on the Buy Skills page will allow you to choose from any of the skills you are allowed to purchase, and can be refunded in the same way as the standard skills.