gitps is an interactive process viewer/killer. It calls internally the ps(1) utility so that's the reason why gitps parameters are in fact ps(1) ones. Running gitps it is self explanatory. Use the arrows, PageUp, PageDown, Home, End, ^N, ^P, ^V, ESC v to move in the list, ^L to refresh it and F10 or ^G to leave. You can change these keys, just read the sections [GITPS-Setup], [GITPS-Color], [GITPS-Monochrome] and [GITPS-Keys] in the configuration file .gitrc.TERM.
See section Configuration Files, See section git, See section gitview, See section gitcmp, See section gitkeys, See section gitmount, See section gitredir, See section gitmatch, See section gitaction, See section .gitaction.