How do I unlock my galaxy centura I forgot my lock screen passwords I have tried pressing power and volume down and still nothing
When power is off, press screen off, volume_down, home for about 1-2 seconds, then keep pressing vol down and screen off but release home key.
It should take you to screen with few options, vol down to go down, and vol up to go up, home to apply option.
Then the rest is easy, use atleast these options, factory reset, wipe user data, wipe user cache, and format system if it has option like that.
NOTE: I tested this on my Galaxy Tab 2 and it worked, you need to google if it's safe to format system with your phone, it's no sin to feel safe.