This guide will help you through the steps necessary to install Raspbian (current version at the time of writing, Raspbian Jesse) onto a USB Flash drive from MacOS (OS X) or Linux (ie Ubuntu). You will need a good quality USB Flash Drive, a USB MicroSD card and a Raspberry Pi (I’m using a Raspberry Pi 3 with WiFi).
In this tutorial, you’ll learn how to squeeze as much performance as possible out of your Raspberry Pi, and prepare it ready to become a live functioning web server. Be sure to follow Installing Apache, PHP and MySQL on your Raspberry Pi once you’re done.
I’m assuming you know your way around Terminal, and you’ve got Raspian installed.