In addition to the Arduino IDE software itself (if not already installed), three downloads are required:First, retrieve the thermal printer Arduino library from our repository on GitHub. Click the DOWNLOAD ZIP button, extract the archive and then rename the uncompressed folder to "Thermal". Confirm that this folder contains the files Thermal.cpp and Thermal.h and the examples folder.
Finally, download the Adafruit "Tweet Receipt" code from its own repository, extract the archive and then rename the uncompressed folder to Gutenbird. Confirm that this folder contains the file Gutenbird.ino. This code is reliant on Arduino 1.0 features and will not work with Arduino 0023 or earlier.
Place the Thermal and Sha folders inside your Arduino libraries folder. You may need to create this folder if it does not yet exist. In Windows, this would be (home folder)\My Documents\Arduino\Libraries. For Mac, (home)/Documents/Arduino/Libraries. And for Linux, (home)/sketchbook/libraries. We also have a tutorial on library installation.
Place the Gutenbird folder inside your Arduino sketch folder (one level above the libraries folder).
After installing the libraries and sketch, restart the Arduino IDE. You should now be able to access the Twitter sketch by navigating through the menus: File→Sketchbook→Gutenbird