well put rock in lava, but on the place where you have 2 rocks put the uper one
Beat the gym
Beat Volkner of the Sunnyshore city gym.
You can't you just have to beat him and get it
Sunyshore city, where the last gym badge will be.
Hearthome's badge
you get the coal badge after defeating Roark in eterna city
if you are looking for the third gym badge i suggest Veilstone city.
in the 1st gym badge
you must beat the eighth gym leader and he will give you the badge.
Once you obtain a badge it's permanently stored in the badge case.
Beat the gym leader.
Get the first gym badge