When logged in click the ‘My account’ in the upper right corner and choose ‘Settings’ from the drop down menu.
Changing your e-mail address:
Choose the ‘E-mail’ input (while in the ‘Details’ tab) and enter your new e-mail address. Don’t forget to click on the ‘Save changes’ button at the bottom of the page.
Changing your password:
Choose the ‘Password’ tab, enter your current and new passwords, and don't forget to save the changes by clicking ‘Change password’