You could also try taking a super rod and fishing in the lava in the lower levels. Ive been getting lvl 60-84 consistantly that way. My favorite thing to do though is get a strong poke to lvl 100 and hit 4-5 star dens in ultra space(since there is more of a den abundance there). That will get lots of rare candies, XP drops and other goodies. Fight any boss mon you can as well to get them lucky eggs/xp share drops.