Having a hard time thwarting opponents' mounts? Don't fret -- here's Rickson Gracie to show what you may be doing wrong. In this video focused on self-defense and basic BJJ concepts, Gracie discusses the main details of the mount.
Besides doing the "upa" to escape the mount, he draws attention to the movement of his own head -- it must rotate in tandem with the "upa." Gracie also does firm grips on his opponent's elbow and wrist in order to remove him at no risk.
Go here if you want access to Rickson's first-ever online course, Self.Defense.Unit.