Click on your name in the top panel to setup your personal preferences.
My Contact Record
Enter your contact details. Pay special attention to your email address and occupation (the latter is often used as a merge field at the bottom of document templates).
It's also a good idea to upload a photo because these appear in the file notes and activity stream.
My Profile
Here you can personalise your Actionstep experience.
Change Password
Make sure you have a strong password that is not easily guessable since this is your primary security measure.