OK...
So, I'm using Mike's revised schematic, I'm upping the 220ohm resistor to a 3.3Kohm, and I'm tying the unused leg on the pot to its middle leg.

To be even more safe I could also:
put a 520 ohm resistor between the output and ground.
And add a 0.1uF capacitor on the input and a 10uF capacitor on the output (both to ground).

Have I got that right?
Do I even know what that means?

Do you (fusto) know how much current the input this is connected to draws?

I'm not sure what current the input draws.
I did get an LED which has a resistor built into it.