This step also takes some time, because it's building an entire operating system. When your build finishes, it's time to flash it onto an SD card for your RPi.
A prebuilt linux kernel image is included in the b2b source checkout. However, if you want to build your own kernel, follow the instructions in <code>$B2G/device/rpi/rpi/README</code>.
== Preparing to flash b2g onto your SD card ==