The Samsung Galaxy Victory is an older phone, so this way doesn't apply to all Samsung devices.
For the Galaxy S3, per say, you need to press and hold Power and Home buttons at the same time for about 2 seconds until you hear a sound or see an animation.
oaky, this trick is only for the the old devices !! Does this work on samsung ace 2 ?? I have samsung galaxy ace never used it much, i was like purchased the phone and as soon as i got new one i throw ace ... so after looking down the post i was thinking to do some experiment with my ace !! so, i am going to try this on ace. So, is it going to work ...... or there is some other ???