I read an old guide from here, tried it and didn't work (english is not my main lang so i might have made a mistake) but anyway, im wondering if it's still working and if it is could make me a quick summary on how to do it, thanks.
SERPENT SIN's skill rotation for normal mode works like simple mode. In this case, you can use simple mode('s skill rotation) in F12.
But it's impossible to make Lighting SIN's normal move skill rotation. So you can't use IT in F12.
If you want use skill rotation in F12, you need to find(or make) skill rotation for NORMAL MODE.