Apple's latest version of its operating system has some nice new features and usability tweaks. Upgrading to OS X Lion from Snow Leopard is pretty straightforward and only costs $US31.99. Here are the steps you can share with others or use yourself to download and install Lion.
These steps will show you how to do a simple in-place upgrade, which means installing Lion on top of your current Snow Leopard OS X operating system. If you'd like to do a clean install of Lion - installing it on a new drive or without carrying over any of your older operating system's settings or information - we have a guide for making your own Lion install DVD or USB drive to do so. But these are the simple upgrade in-place steps. (Note that this process can take a while and slow down your system a bit, so make sure you don't have anything pressing to do on your computer during the upgrade.)
Step 1: Make Sure Your Mac Is Ready for OS X Lion
Check compatibility: The basic requirements for running Lion are relatively modest: 2GB of RAM (system memory), 4GB of free hard drive space, and an Intel processor that is at least a Core 2 duo, i3, i5, i7, or Xeon. You'll also need a recent version of Snow Leopard (OS X 10.6.6 or higher). Most Macs from the last few years will meet these minimum requirements. To check if yours does, click on the Apple icon at the top left of your screen, then "About This Mac" - you'll find the version of OS you're running, the processor, and memory information there.
Step 2: Do an OS X System Update and Update Your Apps
Next, update Snow Leopard to the latest version by going to the Apple icon again and choosing "Software Update"; follow the prompts to update your system, if necessary.
It's also a good idea to update your other software. The App Store icon (an "A" made up of a ruler, pencil and brush in a blue circle) will have a number in red on top of it if there are updates available for your apps. Open up App Store and click "Updates" to get them installed.
Step 3: Back Up Your Computer
Now's the time to back up your computer. For simplicity, we recommend backing up to an external hard drive using OS X's built-in Time Machine (see backup directions). (We've inserted this step into Apple's directions.)
Step 4: Download OS X Lion from the Mac App Store
Click on that App Store icon in your dock (or Applications folder if you don't see it at the bottom of the screen). If you're following these directions soon after Lion's introduction, Lion should be the top app featured on the screen - click on that banner image. If you don't see that big cat, type in "OS X Lion" in the search bar to find him.
Click on the $31.99 price button to change it to a green one that says "Buy App" then click it again to purchase. You should then see the Lion icon in your dock downloading. It's a 3.49 GB file, so depending on your Internet connection, this might be a good time to get up for another cup of coffee or something.
Note that if you purchased a Mac after June 7, you can get a free Lion upgrade. See here for the details on how to do that.
Step 5. Install Lion
Once the download is complete, click on the "Continue" button in the installation window. Agree to the terms and choose to install Lion on your hard drive. You'll need to enter your administrator account password to continue the installation.
Sit back and wait again as the installer works its magic. This should only take a few minutes.
Finally, click the "Restart" button. Once it has restarted, you'll be ready to enjoy Lion's new features, like Mission Control for viewing all your windows at once. For help adjusting to the latest operating system, check out our OS X Lion Survival Guide.