My normal procedure is to check the lights (and stall warning) during my walk around, then turn on the beacon only before start.
On VERY cold days and with a weak battery I have on occasion enlisted the help of someone to check the lights for me after I've got the engine going. Only had to resort to that a couple of times, though.
I open the window (Cessna) for my 'clear prop' call (seen too many guys shout at themselves inside the cockpit...)
If startup clearance is required, then I usually make that call with my handheld. Also use that if at a very busy airport with clearance delivery, as they sometimes give you a taxi delay - no point sitting on the ramp with an engine turning.
Strobes: on upon entering rwy, off upon leaving rwy post-landing.