Trained To Go (TTG) is a slang term often used by criminals which means they aren't gonna flinch when it comes time to commit a crime. For example, in the song "Train to Blow," Lil Jay said the following "I say there’s one thing in mind, Man I gotta get that dough, F*ck it I’m gonna jump a gate, F*ck it I’m gonna kick a do’ Kicking in (TTG), we Tu Tu gang, yea you know we trained to go."
This slang is similar to TTB.