can some one help with my accenta g3 please?

my alarm went off today both with internal and bell box blasting. My husband is in america and all i could think to do was disconnect the black and red battery wires in the bellbox, turn off the mains supply and take out the battery in the alarm panel.
Could someone get me through putting it all back together without me triggering the alarm again. Which order do I do what? it is a accent mini g3 with remote keypad. All help much appreciated.