5. Ice Catcher / Glycerin Coil
One of the most classic ways to get better bong rips is the ice catcher. After a while, glass indents near the mouthpiece of bongs to hold ice became standard. Adding ice to the equation allows smoke to cool a bit further before reaching your lungs.
Another way to cool things down without the need for ice is a glycerin tube. Glycerin can be put into the freezer without expanding and breaking your glass. Furthermore, it retains the cold for a long time so you can get cool hits deep into your session.
You can get one that fits on the joint of your bong, some bongs have them built in and they can be added to customizable tubes as well.