Co-ordinating the movement for 8 legs as the Octopus flips 360 in mid-air is really quite tricky. Accounting for each leg and how it moves in relation to the Octopuses body/head as it flips really confused me at times, I'd either loose one leg somewhere or mistake one for another and skew the motion up.
So, before developing the colour concepts any further I thought I'd tackle this tricky section, and here is how I managed it!
Stage One - Drawings: First I drew and scanned all the key positions for the Octopus as he slips on the soap.
Stage Two - Rough Guidelines: I then colour coded each tentacle so as to be able to track them individually as the Octopus flips.
The front three are red; these are the tentacles that have contact with the soap and so initiate the flipping motion.
The 4th and 5th tentacles either side of the front three are blue, and the remaining three tentacles at the back are green. The head is also marked in pink and the position of the Octopus' eyes are in orange.
I animated each colour coded section of tentacles separately so that I only had 2 or 3 legs visible at a time, this made things a little less confusing.
Stage Three - Fleshed out Guidelines: Next I fleshed out each tentacle to be able to see how they interact with one another; where one overlaps another, if their in the foreground or in the background, etc.
Similarly to before I tackled each colour coded section separately, but this time made regular checks to the positions of the other tentacles... it still looks a bit of a mess here though.
Oh I also added in the motion path of the soap to help with the timing.
Stage Four - Final Outlines: So with all the tentacles and the head in roughly their correct positions throughout the flipping motion, all that was left to do was basically trace over the fleshed out guidelines with a single outline.
This final clip will now become the reference for when I come to animate the real thing. Once I have developed up the colour concepts and have a clear idea of how the Octopus character will look (e.g: if he has an outline, texture, colour, markings, etc) I will be able to simply trace over this clip, frame by frame and concentrate on the aesthetic quality of the Octopus having already got the technical side of the animation pinned down!