First of all, you will need to make a destination list, a destination list is where your accounts will share your posts. Here's a full tutorial on how to do that: www.massplanner.com/knowledge-base/add-new-destination-list/
After that you will need to set up a campaign, a campaign will start sharing your posts into your destination list. Here's a full tutorial on how to do that: www.massplanner.com/knowledge-base/add-volume-campaign/
You can also learn more about Mass Planner with our video tutorials: www.massplanner.com/video-tutorials/
There are plenty of tutorials, take your time to check them out, they will help you to get things done faster.