This tutorial is meant to show you the few steps to change your password especially after logging in for the first time and do not feel comfortable with the initial setup password. Note that you are not able to change your username for your safety.
Log into your Plesk Dashboard.
Go to Edit Profile
Enter your new password or generate one, re-enter it into the confirm password field
Press OK and VIOLA!!! You have successfully changed your password for your Plesk Dashboard.