Name your Mac, making it easier to find it when using file sharing or AirDrop. This is especially nice if your Mac used to belong to someone else. Make it yours by renaming it.
Bring some color back to your Mac! If the Close, Minimize, and Zoom buttons aren't red, yellow, and green, check the System Preferences.
Minimize a window with a simple double-click in the title bar. It's easier to click the title bar twice than to click the yellow button once, because the target is so much bigger.
it's nice to be notified of important stuff but too much is too much! Here's how you customize Notifications, on an app by app basis.
Quickly find the proper item in System Preferences, by searching. There's a reason they put that "Search" box up there-- try using it! Great for new Mac users.
You can preview your Screen Saver choices right there in the System Preferences app. It's much quicker to do it this way.
Your Mac can talk to you, telling you which button you're about to click, which menus are showing, and so on. Very handy if you can't see well, but very surprising to have it turned on by itself. Or by the cat.
Scroll bars should show! They're important indicators of how much material remains unviewed. Apple turned them off; we're turning them back on.
You can set the priority for WiFi networks! This way, you always join the right one, not some sketchy free, open network.