Do this to reset the Vodafone 785 (Turn your Vodafone 785 device OFF first - yes off :) :
1. Press and hold both the Power button and the Volume button past the Android screen to a reddish menu (the Android System Recovery menu-------------)
2. Scroll using the Volume Down key and highlight "Wipe data/ factory reset"
3. Confirm selection using the Power button (simply short press it)
4. Scroll using the Volume Down key and highlight "Yes - - - delete all user data"
5. Confirm selection using the Power button (simply short press it again)
-------------the wiping should commence and complete shortly--------------
6. With "Reboot now" highlighted - following the wiping, short press the Power button to select and reboot/restart the phone.
-------------the phone should restart and allow you to run the first time use configurations-----------
The patter will then be gone after all that.