For the first steps you need to collect the multitouch and WLAN firmware for the iPhone. We cannot legally redistribute these binary blobs, so it is necessary for you to extract them from the .ipsw file and Marvell's Website.
1. Create a folder on the Linux machine named firmware in your home directory.
2. Take out SD-8686-FEDORA26FC6-SYSKT-GPL-9.70.3.p24-26409.P45.tar from SD-8686-LINUX26-SYSKT-9.70.3.p24-26409.P45-GPL.zip to a temporary folder.
3. Take out FwImage/helper_sd.bin and FwImage/sd8686.bin from SD-8686-FEDORA26FC6-SYSKT-GPL-9.70.3.p24-26409.P45.tar and put them inside your 'firmware' folder.
4.Rename helper_sd.bin to sd8686_helper.bin.
You have your WLAN firmware at this point. Now for the multitouch firmware.
5. Create a folder on the Linux machine named idroid in your home directory and take out utils/dripwn from the prebuilt tarball (.tar archive) you downloaded into it.
6. Copy or move the 3.1.2 .ipsw file you retrieved from Apple's Website into the same 'idroid' folder as dripwn.
7. Start a command-line shell (Terminal under Ubuntu) and navigate to the 'idroid' folder you created. You can type cd ~/idroid to do this.
8. Go to this page if you have an iPhone 3G or this page if you have an older version of the iPhone. Copy the VFDecrypt key.
9. In the shell you started earlier, if you have a first-generation iPhone, type the following:
./dripwn iPhone1,1_3.1.2_7D11_Restore.ipsw [the VFDecrypt key you copied]
If you have a iPhone 3G, type the following:
./dripwn iPhone1,2_3.1.2_7D11_Restore.ipsw [the VFDecrypt key you copied]

10. After a certain time has passed, the command will come to an end and you will have zephyr_main.bin, zephyr_aspeed.bin, and zephyr2.bin in your 'idroid' folder. Move these files into the 'firmware' folder.
You have now obtained all the files needed for Android, and you can start to install it.
11.If you have not carried this out yet, install the OpenSSH tool on your iPhone via Cydia.

12. If you have just installed OpenSSH, connect to your iPhone via SSH, log in as root with the password alpine, and type passwd root to change the password for root. Then, enter passwd mobile to change the password for the mobile user.

Do not try to skip this step. All of the iPhone worms out there will harm you only if you haven't changed the SSH password from the default.
13. Take out prebuilt/android.img.gz, prebuilt/cache.img, prebuilt/ramdisk.img, prebuilt/system.img, prebuilt/userdata.img, and zImage from the prebuilt tarball.

14. Use the 'scp' command or an SFTP client to upload all of these files into the /private/var folder on the iPhone.

You may use these commands on Linux, if you would prefer to use scp instead of an SFTP graphical-interface client. If you are in the same folder as the files, enter:
scp android.img.gz root@[ip address of iPhone]:/private/var/
scp cache.img root@[ip address of iPhone]:/private/var/
scp ramdisk.img root@[ip address of iPhone]:/private/var/
scp system.img root@[ip address of iPhone]:/private/var/
scp userdata.img root@[ip address of iPhone]:/private/var/
scp zImage root@[ip address of iPhone]:/private/var/
15. Using the SFTP client or scp, create a folder called firmware in the /private/var folder on the iPhone; after this, upload all the files from the 'firmware' folder you created earlier to it.
If the 'firmware' folder you had created before happens to be in your home directory, you can use the following command:
scp -r ~/firmware/ root@[ip address of iPhone]:/private/var/firmware

(See Page 3)