I have no credit with this guide, I copied it from http://forum.cabalonline.com/showthread.php?t=133008.
This is my skilling guide to all. I have a force archer and this helps me greatly when I want to skill. Alright, so here goes.
1. Get yourself some good adept armor (each piece should give atleast +3 skill exp), and jewelry (DO NOT GET WEAPONS)
2. Find a noob blader and offer him some money (i offered 30k so he gave it to me no questions asked) to get both of his TRAINING katana/sword. I prefer getting only the katanas, I will explain why later on.
3. Wear the armor.
4. Find a good monster you can tank as if you were punching. I did wriggles at lvl 56-60 and it worked perfectly.
5. Get the noobiest SWORD skills you can ex: impact stab, flash draw, etc. (Even if you are a wizard or force archer, it is best to do sword skills, I will explain later.)
6. Level these skills to around 9. Only up to nine it is bad if you do more.
7. Make a hotkey bar of "1. Normal Attack 2. Impact Stab 3. Flash draw."
8. Attack a monster. Make sure that you are hitting less than 10 damage on the monster.
9. Watch yourself slowly kill the monster as your skill level increases fast.
At level 56 i got atleast one skill level from a wriggle, now I tank excavators, and i get around 4-6 levels each one. Even though I was using sword skills, my magic rose greatly.
Explaination: The trick to skilling is how many times you use a skill, not how much damage you do. The reason why I said TRAINING katanas is best, because those hit the lowest on a monster, this is better than shadowsteel adept, because you gain more skill exp off of one monster, experiment if you want, but my way is better with the TRAINING katanas. It should take 5+ min on a monster, so you dont have to waste time quickly kiling many monsters for 10 minutes to gain one skill level, instead of slowling killing one monster for 5 minutes and gaining the equal amount of skill levels.
Have fun with it.