Use a moon stone.
Also, I LOVE MUNNA!
Munna
Ah do you mean how to evolve Munna into Musharna? Cause you cannot evolve Musharna as it's Munna's final form. But Munna evolves by Moon Stone. So just use it on Munna.
Munna does not evolve by leveling up. You need to use a moon stone on it.
Munna into Musharna
Munna into Musharnna
You can use it evolve Munna into Musharna.
munna
It evolves by giving it a Moon Stone.
you find it at the dream yard
Nidorina into Nidoqueen, Nidorino into Nidoking, Clefairy into Clefable, Jigglypuff into Wigglytuff, Skitty into Delcatty and Munna into Musharna.
use moonstone
Moon Stone!