First you start the Tumblr Poster feature
You select the UNFOLLOW button.
Click on Load Following.
Select how many and which blogs you want to unfollow!
Select the delay between the unfollows.
Give your project a name and SAVE your project
In the project overview you click on START!
TUMBLR TUTORIAL VIDEOS:
How To Auto UnFollow Tumblr Blogs On Autopilot