A supisization (pron. sup-ih-sy-zation) generally takes place in a group setting.
The "supisizer" will discretely block his/her cell phone number, and call someone else in the group.
When that person answers their phone, the supisizer repeatedly yells "SUP!?" into the phone. The person who answered their phone has been supisized.

Can also be done in a one-to-one setting, but it's not quite as effective.

When you eat dirt for the first time and leave your family to build a shack in the woods