How do you shotgun beer without throwing up?

I’m rushing a fraternity pretty soon here and am trying to prepare for hazing/drinking in general. I am very familiar with alcohol and drinking as a whole, but not as much when it comes to shotgunning beer.

I can usually shotgun only 1 or 2 before throwing up or feeling sick. I assume it’s from the foam of the beer.

Any tips to shotgun beer better/without throwing up?