First of all, I will try to explain how to bug skills/ attacks with any character* on AIKA Online.
1>> The first way is to use "R". You need to keep "R" pressed and then click on your target repeatedly. This can also be used to bug skills, you got to press your skill's shortcut followed by "R", this should be enough.
2>>The second way uses any directional (W,A,S,D,Q,E) and the shortcut where your attack/skill is, in my case the normal attack is on the key "1". You need to quickly press any directional + attack or any skill that you want to use, this can be very exhaustive, but with time and pratice you'll get used to it.
3>>The last one is similar to the second, using any directional/ Your shortcuts/ Mouse ( click). Do the same thing from the previous item, but add another step, the clicking part. So, you'll press W or any other directional + Attack/skill+ Click anywhere except on the oponent *As Fast As You Can*
*You gotta keep in mind that some skills can't be bugged, for example "fireball" or "meteor" , to put it in a nutshell skills that need to be charged won't bug as you want them to, the maximum that you'll get is to cancel the motion, but you'll still need to wait the launching time of the skill.
Have Fun and Good Luck