For brief instructions, check out Getting Started with Overdrive Help

Detailed instructions:

Libby: For Android & iDevices
Older Android Devices: ebook & audiobook instructions (Kindle Fire, Nook Color, Google Nexus, Samsung Tab, etc.)
Older iDevices: ebook & audiobook instructions (iPad, iPhone, iPod Touch)
Kindle reading devices: ebook instructions (Kindle Touch, Kindle Paperwhite. Kindle Fire owners please use Android instructions.)
Nook reading devices: ebook instructions (Nook Samsung Galaxy owners please use Libby instructions)
iPod/mp3 player: audiobook instructions

You can use Hoopla through a web browser on your computer, or through an Android or Apple app.

Instructions on using Hoopla on your computer’s web browser.

Instructions on using Hoopla through the Apple app.

Instructions on using Hoopla through the Android app.

Detailed instructions for all devices & browsers