A little trickier to explain in a single gif, so I'm sharing a process video. Pose to Pose is an animation workflow process where you draw “Key Poses” first, then adding breakdowns and inbetweens.
Here I roughed Hitmonchan’s start pose, anticipation pose, and final pose before experimenting with inbetweens and timings. Then I finally moved on to clean and color.
Animators often combine Pose to Pose with “Straight Ahead” animation techniques (tomorrow's tip). I personally like to do pose to pose for primary body movements, and use straight ahead techniques when adding overlapping action like hair and cloth.