Two things you can do, i'll start with the simple:
Try to think what passwork you would do now, or try over and over until you get it.
If it's not helping, or you have no patience, the best and "safe" way is to wipe all your data (Resets your phone). WARNING!!! this method means you're gonna lose ALL your information.
If you are not worried of losing all your information on your phone - then it is the right way (that way resets your password either).
To reset your phone you should Turn off your phone, wait few seconds, then press on: power button+Volume Up+Home button at the same time, right after the white logo of Samsung Shows up leave the power button. you will get into Recovery Mode.
Choose "wipe data/factory reset" and after that choose "reboot system now".