ok I DO have ONE hot tip.
So. You're like me. You have ideas and you want to see characters move around in sync with some audio. But also you need to cut as many corners as possible. BUT ALSO you really want it to feel good to watch to justify the effort.
My tip is this: use tweens but as few as humanly possible.
To explain: so we got these key poses we wanna use while somebody says something
That's 3 drawings!
If you draw out a whole scene at this rate, you'll get the point across! This totally works! You can have all kinds of cool poses and expressions and it will still be an unreasonably large number of drawings, and an impressive feat to finish!
BUT since we're already here....why not trick everyone into thinking it's "smooth" by making THEIR brain do HALF the work, at LEAST.
^ That right there is only 3 additional drawings!
Tween Type 1: bridging the gap
so the difference between these 2 frames is huge, and as a consequence playing one right after the other feels choppy.
Now I haven't explained the second kind of tween yet, but the way we decide between them is by asking ourselves, "how controlled is this movement, and where is it fastest?"
This guy is unfolding their arms and then placing a hand on their hip. This is a more controlled motion, because the limb stays close to the body at all times, where there's not much room to swing around.
Also, if you do this in real life to test it, the two slowest parts are separating your arms at the beginning, and then resting your arm on your hip. Between those two parts, it's mostly just your arm swinging into place relatively fast.
The fastest part will be easier for your brain to fill in for us, so the tweens are only added to the slow parts.
The arm starting to unfold, and the arm slowing down to rest on the hip.
The second screenshot, depicting the "end" of the movement, is overlaid onto the NEXT frame rather than the previous, because it will need to look very close to that for your brain to process the new pose properly.
These 2 new drawings have created just enough of a bridge for your brain to register it as a movement rather than two separate images.
Tween Type 2: overshooting
This kind of tween is used for faster, less controlled movements, or anything that "squishes." Here I use it for the guy bringing his arm up, and his eyebrow moving.
Once again overlaid onto the frame AFTER this tween, so you can see the "overshoot" effect.
Since the arm is out in the open air, it will swing with the momentum it took to raise it, and the guy's musclea will need to squeeze it back into the place they intended to hold it at. So it moves past the final resting pose (overshoots it), because it is too fast to slow down before it.
Overshoot is kind of the opposite of bridging the gap. Where bridging the gap shows you something starting to move, and then slowing down; overshoot shows you something winding up (omitted for this chill guy, but it's a frame "pulling back" on the pre-movement pose where the frame I did add is "pushing" on the post-movement pose), and then struggling to come to a complete stop.
But just like bridging the gap, you don't have to draw he middle because the movement is fast, so your brain wouldn't have paid attention to it anyways.
So yeah thats how I play tricks on people's minds without REALLY animating! Go nuts!
Since the tweens are onscreen for much shorter times, don't be afraid to let them be messy, so that you can try out a few different variations to see which looks right. I redrew that arm coming to rest on the guys hip 2 or 3 times, and it was originally supposed to be an overshoot, but the bridge ended up looking better!
theres actually a name for this! this is actually not tweening, this is the step before — the breakdown phase!
Breakdowns are the between frame between two keyframes. Depending on how much you favour one frame or another, you’ll change the feeling of the animation when you inbetween further.
it’s an important step that defines the feeling of the motion!
Anyway I shan’t say much more than this since you’ve already given some great examples of different ways to approach a breakdown, but this is a nice video on the topic if you want to learn more:
