This is not a real HOW TO, it’s a two-step guide for setting up a Raspberry PI (with a wifi usb adapter) in order to create an easy-to-use TOR proxy on a WiFi Access Point.
Two simple steps:

1. Create a Wifi Access Point on your Raspberry following this guide: https://learn.adafruit.com/setting-up-a-raspberry-pi-as-a-wifi-access-point/install-software https://www.raspberrypi.org/documentation/configuration/wireless/access-point.md
2. Install and configure TOR using this git repo: https://github.com/sarbyn/tor_box/blob/master/README.md

So simple!