Use your wingtip lights to let others know your status.
Position lights or anti collision lights?
(Real world) Any time you start engines on any aircraft you should have the position lights on. This lets ground crews and vehicles know that there are aircraft engines running. We can't hear very well anymore due to years of working around running aircraft...and have hearing protection on.

Prior to taxi, turn on anti collision lights. Everyone knows you're ready to go now.
