Ranger roll a t shirt.

1 lay shirt flat
2 fold bottom several inches up/inside 
3 fold in sleeves 
4 fold rest of shirt in half
5 from the top roll shirt tightly 
6 use bottom fold as ‘bag ‘ for shirt.

This is definitely not original to me. As I lone to travel and bring a single bag I can see this being an important hack.

Ranger roll video