1. Open calendar Preferences. Select Preferences in the menu at the top of your screen.
2. In Preferences dialog select Accounts tab.
3. In Accounts tab click on "+" button at the bottom to add new account:
4. In Account Type select CalDav:
5. Enter your hiTask user name and password.
6. In Server Address field enter secure.hitask.com/calendar/<username> where <username> is your hiTask account user name. For example if your user name that you use to log in to HiTask is john, calendar address will be secure.hitask.com/calendar/john
The dialog will look like this:
And that's it!
Please note that it may take a minute until tasks appear in your calendar.