Click "Settings" at the top and then "Users" in the left hand column. This will take you to the page below where you will see a list of your current users. Click "New" as circled below:
You will be led to the page below, go ahead and fill in the details of the person you would like to add as a new user, when you're finished, go ahead and click "Save":
While the email is being sent to the new user and they are setting things up from their side, their status in Heydoc will register as "Unvalidated" as below:
Once the new user receives the email which will look something like this:
They can click "click here to create your account" it will take them to a page where they need to enter a password and then reconfirm their password as below:
Once your patient has set up their password, they will no longer appear as "Unvalidated".
Please note that you can only use an email address once. You can never have more than one user with the same email address.
If the email has not been received by the person you are trying to add do confirm if they have checked their Spam folder as well as their main Inbox folder.