did you try to google?
I am not responsible for the below if you damage your phone
1. Prepare custom Apple iPhone RAM disk. Internet has tons of FAQs how to make it (for example with help of iLiberty+). Mount your RAM disk /dev/rdisk0s2 and delete file /mnt/mobile/Library/Preferences/com.apple.springboard.plist. This is a config which tells Springboard “passcode: on”.
2. Using any utility get your iPhone into “Recovery Mode” and after that upload RAM disk using something like this:
(iPHUC Recovery) #: filecopytophone Bypass_Passcode.bin
(iPHUC Recovery) #: cmd setenv\boot-args\rd=md0\-x\-s\pmd0=0×9340000.0xA00000
(iPHUC Recovery) #: cmd saveenv
(iPHUC Recovery) #: cmd bootx
3. Then reboot your iPhone and that’s it: protection by the password are not present anymore.
Congratulations you have hacked your first iPhone…