Powering a Arduino Nano

Hello and thanks for reading.
I have a simple question.
If you have built projects with an Arduino Nano, how do you provide external power to it?

To add some detail:
I built a small project for a FM radio using a Nano.
From the Nano board, I'm powering the FM radio module (3.3v) and an audio Amp circuit (5v)
The project works fine when powered by the USB cable, but:
How can I power it from a device I can plug in the wall (I don't want to use batteries)
I've read many posts about powering Nano's, and there is a lot of talk about theory, information about max voltage the Nano can use, etc.
But I want to know, no kidding, what do you use to power it?
Specifically, what device do you use and how do you connect it?
Pictures or links to devices would also help if you are able to provide.

I have a old "Wall Wart" that provides 12 Volts and 1 A, I'm thinking if I just cut the end off, and take the positive wire from it and connect it to the VIN pin, and take the negative and connect it to the Ground, then I should be ok, but I wanted to hear from those with more experience.

Thank you for your help.

What I usually do is find an old phone charger that uses a USB cable to charge the phone. Those little Apple cubes are nice as you can switch out the USB cable for one appropriate for whichever Arduino you're using.

thank you

I use a 5V regulated power supply connected to GND and 5V. I have loads of them from 1A wall warts up to 5V 30A power supplies.

Steve

You don't want to use the 12V supply unless your Nano is drawing very little current. The Nano's built-in voltage regulator would have to drop the 12V to 5V, and it has no heat sink to deal with the heat generated when lots of current is flowing. Any standard USB charging wart is perfect for this. You have a regulated supply at 5V, and can plug it into the USB connector of the Nano with a USB cable.

Get into the habit of collecting power supplies from electronic equipment that's being discarded. That way you will always have a power supply for any projects that you make in future.