1. Get ready your Raspberry Pi Type B/B+ image and 8GB SD card.
2. Download the 3DPrinterOS Raspberry Pi Type B/B+ image.
3. Unpack the file from archive and install it as usual Raspberry Pi image.
Usual installation of Raspberry Pi image
Easy Raspberry Pi guides:
Windows/Linux guide
http://elinux.org/RPi_Easy_SD_Card_Setup#Using_the_Win32DiskImager_program (Use Win32DiskImager, just select IMG and write it to SD card)
MAC guide
http://alltheware.wordpress.com/2012/12/11/easiest-way-sd-card-setup/
OR
Official Raspberry Pi guides:
Linux guide
http://www.raspberrypi.org/documentation/installation/installing-images/linux.md
MAC guide
http://www.raspberrypi.org/documentation/installation/installing-images/mac.md
Windows guide
http://www.raspberrypi.org/documentation/installation/installing-images/windows.md
Should you have any questions please do not hesitate to contact us.