My bro has a Cleric...The best way to make lots of AP is to make an Alliance whit Gladiators/Rangers and fully geared Clerics +(Chanters for buffs)...
Make 2 to 4 Clerics +1 Chanter and 4-6 Gladiators/Rangers is perfectly matched to kill any Asmo in game! Plus if u stay together u will receive x2 to x4 more AP then being away killling solo. Thats how my bro made over 100k AP in less then 1 week killing at least 2 to 4 Asmo a day!!!
->Imagine killing during Event!!! RvR ->100 vs 100. 250k AP Guaranteed!
A good way to earn AP is to make another ASMO or Elyos depends what is the race of your main char. And train that Asmo/Elyos to egual rank....For example if u are rank 8 with your main train your Asmo/Elyos (lv 55) to rank 8. Then u just kill the ASMO/Elyos one (lv 55) till he gets to rank 9...And each time u reapet the exact same thing from the begining.
*Note: Its better training an ASMO/Elyos to highter rank then u are
In order to receive AP more quikly.