Transistor as switch with "Incandescent Lamp as load"

[mod]

usually i used Led as load with dc voltage for input.
now, i'll use incandescent Lamp as load, with dc voltage. what i'll do first?

and one more,
anyone have a diagram circuit of transistor as switch and use potentiometer on the circuit?

 

[(*steve*)]

You do it exactly the same way except you don't need a series resistor.

Ensure that the circuit can cope with the low resistance of the bulb when the filament is cold.