In my real world, and sim operations, I use the red, rotating beacon(s) at all times, along with the navigation lights, at all times.
White strobes go on when entering a runway environment, and stay on while airborne, and go off when leaving a runway environment.
Landing lights are purely discretionary on smaller aircraft such as light Cessna's and Beeches, but for commercial applications, and for my airline sim flying, my landing lights are on when entering the runway environment, and stay on below 10,000 feet. They are then turned off above that, and turned off when exiting a runway environment.
Taxi lights are on as soon as you start any movement on the ground, even in daylight conditions, and go off when airborne.
These are just my own operating procedures, and I'm sure you will see many different practices throughout the world.
