Gomu Gomu no Fusen 

Like a helium balloon, Luffy's body becomes highly buoyant.

Gomu Gomu no Gigant 

A method where Luffy increases his size till he resembles a real giant

Gomu Gomu no Bajrang Gun

The Gomu Gomu no King Kong Gun adaptation for Gear 5

Gomu Gomu no Mogura Pistol

When Luffy strikes the ground with his fist, a tendril-like extension of the ground appears nearby.

Gomu Gomu no Dawn Rocket 

As he dives into the situation, Luffy utilizes his newly awakened abilities to further bend the structure.