A pose is defined as the data set of pos/rot/scale info of all or some joints in the skeleton hierarchy.
Pose Manager is used to save/load/apply poses, it can persist the data on the disk;
Toggle Pose Manager
Just click the "G" button on the GUI-Main panel; the new panel shown on the left is the GUI for PoseManager;
Click the `Load’ button will bring up the "open file dialog", by which you could select an existing pose file to load or switch the current in-use pose file.
Click the `Save’ button will save the current in-use pose file, if there's no underlying pose file yet, this action will prompt to create one;
The menu displays all the poses in current pose file.
For each pose, there’re 4 buttons.
The first one is the pose’s name, click the button will Apply the pose to current model.
The second one is delete button, but you need to save to write the change into disk.
The third one is overwrite button, will overwrite the current pose of model into this data.
The fourth one is rename button, will change the pose’s name.
Be noted that, when PoseManager is activated, you cannot modify the joints. It means you need to do the pose first before opening up PoseManager;
When you click a joint, the joint and all of its descendants joints are selected (will be tinted green), you could also add/remove single joint by Shift+LMB.
When you decide which joints are to be saved, click the "New Pose" button, it will prompt a pose name, after confirmation, the data of selected joints will be saved under the given name.
Quickly add keyframes with Pose
There is also a brief video showing how to use Pose Manager;