A bit more security
By default, when you draw your pattern on the lock screen you'll see lines connecting the nodes so you know what you're drawing. However, this is like turning on "show password" when you're typing it in. It's good for avoiding typos, but anyone in the area can see what you're doing.
In your Android gadget, go to Settings >> Security and uncheck "Make pattern visible." On some gadgets you might find it under Settings >> Lock Screen. Now all a spying thief will see is your finger moving quickly over the nodes, which will make it much harder to remember your pattern.
When you're in your security or lock screen settings, you might also see the "nuclear" option. It's called "Auto factory reset." If this is on (and some gadgets have it on by default), you only have 10 attempts to unlock your gadget and then it wipes itself clean.
This is a good defense against a hacker trying your pattern or password an unlimited number of times. However, if you tend to fumble your login information, or you have little ones around who like to play with gadgets and don't understand warning messages, it might be best to turn this off.
Bonus: Smart Lock
Since we're talking about lock screens, there's a wrinkle on some newer Android phones called Smart Lock (usually under Settings >> Security or Settings >> Lock Screen). Say you connect your phone to your car's entertainment center or a wireless headset using Bluetooth. With Smart Lock, you can set it so that the lock screen doesn't activate while your phone is connected to the trusted device.
You can also set up trusted places, trusted voices and on-body detection. As long as you have the phone with you, or in a place you know is safe, such as your home, you don't have to mess with unlocking the phone every time you want to use it.