I don't know what others do but most my wolves have Furmus, Deer, Dustraven, Monstropod or some other pebble companion on them. Also I release wolves that I don't want at level 10 10kp and 1kb each release. Also selling Trinkets from spamming explore and those money companions as they usually give some form of trinkets too
Everyone has their preferred method. But ones I have found to be effective consistently are completing activities, leveling and releasing wolves, selling trinkets in inventory, cooking and selling food in inventory (nutty feast is my preference for that), selling random things on the flea market helps supplement but isn't very consistent for me. Also as you play, you will complete achievements which also can reward pebbles.
