The first gif shows the giver’s hand going in a wider, circular motion, whereas the second gif shows the giver going in more of an up and down motion. Remember to calibrate the amount of pressure, using feedback from the receiver.
“For another technique, make a loose fist. Place the flat surface of your fingers, between your second and third knuckles, against her vulva, and wiggle your fingers as you move your hand side to side. This will stimulate her vulva and clit with a rippling sensation. You can do the same motion while also flexing your wrist up and down, which doesn’t induce orgasm for many people, but does give a pleasurable mix of swiping-circular sensations.” – Excerpt from Beyond Satisfied by Kenneth Play, Chapter 7: Fingering, Different Strokes