The Confused Octopus

The process of getting my head around 3D animation is slowly but surely making progress. In uni the other day we had to design little octopuses, and then make them float up down in a relaxing manner... Here's mine -

I was very satisfied with the way the octopus looked, as from all angles he did indeed resemble a happy-go-lucky cartoon squid, but unfortunately his movement didn't go quite as smoothly. Rather than bobbing up and down, he kinda shoots into the air and then falls back down again. Just to add insult to injury, then all his legs fly out in the wrong direction and he, erm, gets himself into a bit of a mess.
However, by confusing this poor octopus I think I've learnt a little more about 3D Studio Max. Hopefully within a few days/weeks/months/years (let's hope it's not years, eh?) I'll have cracked it!