Guide: Removing desktop to run headless (Raspbian Jessie 2015-09-24) (self.raspberry_pi)
Start out with entering: sudo raspi-config into the terminal. Once you get into the menu select boot options and make the pi boot to console. Optionally you can overclock Then: sudo reboot now
When it's back up run: sudo apt-get remove --auto-remove --purge libx11-.* this will remove all the packages that start with lx.
Remove some rather large packages with: sudo apt-get remove --purge wolfram-engine libreoffice libreoffice was added to the Jessie release, since we're running headless we don't need this.
Run: sudo apt-get autoremove to clear out the rest of the packages we no longer require.
Run: sudo apt-get update && sudo apt-get upgrade
Reboot and finish setting up your headless pi
Note: I wrote this guide not 5 minutes after I did this to my pi. So I am open to criticism and optimizations. If anyone would like an image I could pull one off of the SD card on request. I did this on the original raspberry pi B with 256mb of ram. Someone correct me if I'm wrong but this should work across all versions.