Windows 8 includes a new feature called Picture password, which allows you to authenticate with the computer using a series of gestures that include circles, straight lines, and taps. Enable this feature if you want a new way to access your computer or have a hard time with passwords.
Open the Windows Charms.
Click Settings and then More PC settings
In the PC settings window click Users and then select Create a picture password
Bonus tip: A four digit pin password can also be created and used to access your computer.