A charcoal disc is placed on a heat resistant surface . If you do not have a heat resistant surface, sand in a bowl can be used.  Once you have that completed, I usually recommend a small amount of salt be placed in the round divot on the top of the charcoal to help stop the oils in the resin from extinguishing the heat source early.  Place desired amount of resin pieces on top of the charcoal.  If this is the first time you are burning a gum resin then I suggest you only place 2 -3 pieces on to ensure that you do not over do it in, it is easier to add more resins afterwards then to take some off if the fragrance is overpowering.  The Charcoal Discs will burn for 30 - 45 mins.