in simple:
you burn execftps to CD
load it up, plug in your PS2 to your network and boot FTP program onto your PC
then make a folder in MC0 called BOOT
in that folder place the execftps elf and Ulaunch Elf but rename ulaunchelf to BOOT.ELF
then boot your PS2 into Dev1 mode and setup launchelf
then boot execftps and transfer the MI firmware elf to the MC BOOT folder (you need to extract the firmware from the .CUE/.BIN file)
reboot your PS2 and use launch elf to run the update
Im sure there are loads of in depth tutorials for most of this so search
regards,
Danny