Cylinder ceramic Wax Melter or Wax Warmer. Light on the regular soy wax candle in the bottom part which will slowly warm up the top part where you put the Wax Melts.
This will make your Wax Melts slowly diffuse their extraordinary scents as it is not burned by the fire but warmed up. You can choose the amount of Wax Melts you prefer depending on how strong you want the scent to be.