Sure you can make a preset of Amaterasu :3 Infact there are many other users who have made some.
If you like you can even download them and use them yourself. Just be sure not to run around claiming the design as your own

although I am pretty sure you're not that type of person

. Here is one if you would like to check it out

It might save you the work of making a whole new one from scratch.
http://browse.deviantart.com/?q=okami+preset#/d4pbuy0This is the download to that one:
http://www.mediafire.com/?u4eicol76zr4901If you download it all you have to do is place the files into your "My Presets" folder into one of the empty "preset_1" "preset_2" etc folders then enter the game and on the menu select "Tools" then "Preset Maker" and export it in the "V" option at the top and you should be able to use it in game once you enter the character editor and then select the "V" option at the top and put on your preset on to your character by selecting the preset option from there.
If you need any help or advice feel free to private message me
