Green’s Dictionary of Slang

go it v.

1. [late 17C; mid-19C+] to move at great speed.

2. [late 18C+] (also go it hot) to commit oneself fully, usu. to a course of self-indulgent pleasure or as in a fight.

3. [early 19C] to work as a prostitute.

4. [mid-19C] constr. with for, to offer one’s support.

5. [mid-late 19C] to fight physically or verbally.

6. [late 19C+] (Aus.) to accept, to believe in.

7. to masturbate.

In phrases

go it blind (v.)

[mid-19C–1900s] (US) to enter on an undertaking without proper preparation or planning.

go it hot (v.)

see sense 2 above.