If you mean a non-combat pet then they don't gain experience at all. They don't need to as they don't fight. In Mists of Pandaria (the next World of Warcraft expansion pack), they will probably gain experience with the new pet battle system. Although, exactly what that entails is not known yet.
If you mean that you're a hunter, and the beast that you've tamed doesn't gain experience, it does. It levels with you, but only if you have it summoned. If it is in the stables or you have not summoned it, it will not be the same level as you were when you last summoned it. As soon as you summon it, it will become the same level as you.
well you have to wait till your bin pet has enough exp to jump on
you do missions 10% of the exp is given to him
Have your pet fight along side you. They don't have to even attack but as long as they are out they will gain 10 exp from a mob about the same lvl as you. (only gain exp if mob dies)
You can go to your friends house and clean up or do missions.
well you just play and look afder it
buy the pet, and dont let it go to the family member. if anyone thinks this isnt a correct answer, feel free to correct it
It's pretty easy, if you have the time for it. It depends on what type of your pet loves. Just do the gobbler drop games about more then 10 times and after it feed it, its favorite snack and it will double your exp for your pet. After doing this a right amoutn of times your pet will be an aadult in no time.
while the guard isnt looking take the coconut and the elastic band and put them on a stick
Currently you stop gaining levels at 30 but keep getting xp
A tera Pet is like a pokemon.... there isnt really much different than pokemon except for it's graphics,the creatures, and items ..
Yes, as there is with any pet animal.
You need any pet tool and if you saw a pet use the pet tool