How to install kernel sources

I 'm running Angstrom distribution (console only) on BeagleBoard-xM. Image was build on Narcissus , with Bootloader Files (x-load/u-boot/scripts) added. I noticed that usr/src directory is empty. I intend to install kernel source packages. For this reason, I downloaded Linux kernel 2.6.32 from https://www.kernel.org . What should be my next steps? I 've been searching for days, but I didn't find anything. Any help would really be appreciated.