When trying to explain how a particular feature works on a Mac to someone who isn’t in the same room as you, sometimes only a video will do. A handful of applications exist to help you perform this task, but they've all been blown away by a newcomer, ScreenFlow.

With it, not only can you record actions on your screen, you can also capture video from your iSight camera, blending them together to create a unique, highly polished film, ready to be uploaded to the Internet—as long as your Mac is running Mac OS 10.5 Leopard.

There's a lot you can do with this application. We'll show you some of the basics to help you get started quickly, then follow up with some more advanced power-user tips later on. So download a trial copy and let's get started.

Difficulty: Medium

What You Need: ScreenFlow ($99.99, www.varasoftware.com, or get a demo version here), G4 or Intel Core 2 Duo Mac (Intel recommended), an iSight camera (optional), and about 30 minutes of time.

1. Installation Station

Move ScreenFlow from the Downloads folder to your Applications folder, or the software may not function properly (all commands in the menubar could be grayed out, for example). Once that’s done, launch it. You’re greeted with a simple semitransparent window that holds three options. The first two let you record video from your iSight camera (if you have one) and give you the ability to record external sound using your Mac’s built-in microphone or any other mic hooked up to it. Let’s keep these two off for now.

2. Oh, Driver?

Select Record Computer Audio. ScreenFlow will ask for permission to install a special audio driver that it needs for perform this function. Allow it to do so, and enter your administrator password when prompted.

3. And…Action!

Time to record! Click the big red button. After a countdown, ScreenFlow will begin recording your entire Desktop. Perform various actions like launching other apps, selecting commands from the menubar, using keyboard shortcuts, opening and navigating through folders, even use Fast User Switching to move to another account. ScreenFlow will record it all. When you’ve finished, press Shift-Command-2 to stop the recording.

4. Honey, I Shrunk the Screencast

Click to embiggen.

ScreenFlow will then open up its video-editing window. The first thing we need to do is reduce the Canvas area: By default, the Canvas matches your screen’s current resolution, which would be much too big for the Web. Also, you most likely only need to focus on a small section of the interface anyway, so cropping can help.

Click the Resize button located at the lower-left of the Preview section. Reduce the size until it’s somewhere within 640x480. Click Apply to set this change.

5. Tweak a Little More

Click to embiggen.

Clicking the Preview section selects your video clip. You can then drag it until you can see the section you wish to focus on. To the right are the Video Properties. Drag the Scale slider to the left to fit more of your Desktop image in the window.