How do you time fart?

[{RECON}Nexus_[QS]]

It tells me I need to use it but doesn't say how.

[Moon Rabbit]

On a controller, hold down L2/R2 and hold the analogue sticks in a specific direction depending on which effect (both left to reverse time, toward each other to pause).

On keyboard it's 'T' with the analogue controls replaced with WASD and the ARROW keys for left and right sticks.