In order to get started please make sure you are logged into the portal and you have clicked on the license number you want to start auto-rotation on. Once you get there look for the button Enable Auto IP Renewal (See below)
Once you click on this button you will be able to enter a number between 1 - 1440. This is in reference to minutes. The lowest you can have is 1 minute and the highest is 1440 minutes (which is 24 hours). If you want 6 hours then you need to multiply the amount of hours times 60 to get your answer which would be 6 X 60 = 360. So for your IP to change every 6 hours put in 360 and press Set Auto-Renewal Time Interval.
You can change this at anytime and also check to see what interval is set by going back to this page. The time you have set will show up in the box and it will say the next time it will renew the IP.
If you have any other questions be sure to ask us.