1) make sure your Nokia N810 Internet Tablet is running on the latest firmware (Diablo) ,The OS2008 Feature Upgrade, based on Maemo 4.1 (codename: Diablo)
2) make sure your N810 has at least 110MB of free space on your device (internal memory or external miniSD card)
3) Download and save the android.img.bz2 image file to your device (internal or external storage).
4) Download and save the android-installer.deb file to your device.
5) Install the Android Installer file (android-installer.deb ), such as following picture:
6) Reboot device,Start Android from the "Extras" dual boot menu :
7) OK,enjoy yourself Android Running on Nokia N810