To get a bigger vapor cloud, the first important thing to note is the use of e-juice. However, as said above, you should fill the vape tank with e-juice, which contains a large amount of VG content. Then, the vape mode must have a watt rating above 40 watts. After firing your mod, ensure the airflow is open to allow unrestricted airflow to the sub-ohm coil. Then, you have to practice exhaling into vaping mode before you inhale. Thus, more air is forced into the rings resulting in large clouds.