The practice portal password for the practice can be created by following the below steps.
Go to 'Admin' >'Design & Sign' > 'Practice Portal'. See below:
You will then be able to create the practice portal password. It is very important to make this as secure as possible.
If you already have a password set for the practice you can also update it by entering the current password and then entering the new password and selecting 'save'. See below: