Best leveling guide?

So, i have 3 chars at 120 lvl, (sham, priest, dh) out of which the first two were both leveled up with a boost and the third was brought to 120 while helping a friend. I play only arenas out of endgame content and i would love to play all the healing classes. My problem is that i cant stand leveling. I came back after an at least 6 months break from wow and i want to level my monk who is 48 level atm to max. Could you please forward me or link the "best and fastest leveling guide" according to their opinion? Thanks in advance.

Is it joke or what?

Take your eyes out and wash them bruh.