Bone Scaling Animation

1. Switch to animation mode

Auto Keyframe

1. Turn on the auto keyframe button in the toolbar on the left side of the timeline panel.
2. Move the playhead to where you want to add a keyframe.
3. Select a bone and modify its scale.
4. The keyframe will automatically appear on the timeline.
5. Drag the playhead with the mouse to observe the animation.

Manual Keyframe

1. Turn off the auto keyframe button in the toolbar on the left side of the timeline panel.
2. Move the playhead to where you want to add a keyframe.
3. Select a bone and modify its scale.
4. In the property panel, the small flag after the scale property turns yellow. Click the flag button to manually add a keyframe.
5. The flag turns blue, indicating there is a keyframe at the current playhead position.
6. Drag the playhead with the mouse to observe the animation.