Google: iRecovery
iRecovery is a command line tool that requires you to install a library. For this, you are required to understand how to use theterminal. These instructions are *very clear* if you understand the*terminal*and shell commands. If you do not, this is not for you. Find a windows computer or someone that can help you. Teaching how to use the OSX term is way beyond the scope of this guide.
Download and extract*iRecovery. This is a console app to be run interminal. Extract it with finder.
Copy libusb-0.1.4.dylib to /usr/local/lib and chmod both iRecovery and the dylib to 755 using chmod 755 /usr/local/lib/libusb-0.1.4.dylib and chmod 755 iRecovery.
In*terminal, run iRecovery -s
At the iRecovery prompt, type: fsboot
Wait,*iPhone*should boot. If not, type fsboot a second time.
ctrl-c or close the term. You are done with iRecovery.
Here is a more detailed set of instructions by Max:
1) Download iRecovery
2) Place both files on the Desktop
3) Open*terminal*and type cd ~/Desktop
4) Run command chmod 777 libusb-0.1.4.dylib
5) Run command chmod 777 iRecovery
6) Run command defaults write com.apple.finder AppleShowAllFiles TRUE
7) Run command killall Finder
*Navigate Macintosh HD > usr > local > lib
9) Copy the file libusb-0.1.4.dylib into that folder
10) Open a new*terminal
11) Drag-and-drop the iRecovery file into the*Terminal*so that you get a shortcut to it.
12) Append -s to the end.
13) setenv auto-boot true [Enter]
14) saveenv [Enter]
15) fsboot [Enter]
13) Run command fsboot (i had to do it twice)
14) If the phone starts up locket once again, just run through steps 10-13 again.
15) When done, open*terminal*again and type defaults write com.apple.finder AppleShowAllFiles FALSE
16) Then run killall Finder once again and your done!
You have to run these commands from iRecovery, if you don't once you reboot your phone it will be in Recovery Mode.