Well, I will post my method and see what other people are doing and maybe there is a better way.
First, this is for wolves.
I have a lvl 60 se and a level 57 bd. SE provides buffs and bd is the one with the wolf.
I buy a low grade sword like a falchion. For the first 10 levels or so I head out to level 35 or 40 non aggro mobs (try to find nonsocial as well).
A bd is ideal because they have hate to get the initial aggro and they also have fantastic melee buffs that effect party members as well as pets.
The SE has great buffs for pets as well. I would prefer a prophet though.
Pretty much get top wolf gear, food, alicrity pots and head on out. I cast hate, hit the mob with my crappy sword, have wolf attack and go on from there. Of course the wolf will still die from time to time but pet brez's are cheap.
After that, I head to alligator island which is a good next step but there are better areas to try.
carefully, helps to put heal pots in his/her inventory too. both types. Best pick mobs close to your wolf's level, and use skills and such to do minor dmg and gain hate/aggro.
Best to pick spots with non-aggro mobs and those that are not social.
Watch out for griefers, they will spot you leveling your wolf and kill it at range (spell or bow) just to piss you off... only reason mine is now sitting in my warehouse.
try not to get it killed LOL
anyway if someone need a wolf to kill something you need to recheck skills i dont even know why pets are ingame they are totaly useless atm
bro dont get me wrong i like pets a lot even ingame
but they only get them self killed just a waste of time and adena's
The C3 aggro changes are what killed pet leveling for a lot of people. Before C3, pets would never pickup aggro unless they were actively attacking the mob. They would still get wacked by special skills or spells and the 'swapping' targets behaviour associated with them. But avoiding those mobs was still possible.
Now with pets taking aggro to an insane degree, it is much harder to keep them alive. (NC really should have beefed up the pets HP, PDef and Mdef when they made the aggro change at the least.) You can still level (with) them, but it takes a bit more care.
What I do (OL+Wolf) is find clear spot next to where mobs spawn and there is low social/aggro. There should be no mage or archer mobs and the melee mobs there shouldn't be 'nuker' happy if you need to pull them any distance.) (Slow mobs like Golems or Ghouls tend to be nuker happy.) I use a single ranged attack (Drain) to grab a mob and aggro it, let it come to me then me and the wolf both beat it down. If needed I will run out to grab a mob and pull it back a bit.
So far I have found enough places that I could level all the way into the upper 60's easily enough with the wolf.
bro dont get me wrong i like pets a lot even ingame
but they only get them self killed just a waste of time and adena's
They really don't die all that often, if you have a skill that can keep hate.
I've heard of several people, who use a wolf as a secondary DD to assist them in PvE. That means they're not useless.