Launch the Pro Tools software program. Create a new session by selecting in the menu at the top:

File...New Session

Or use the Apple shortcut Cmd-M.

A new dialog box will pop up that looks like this:

Type in a name for your project and choose the location on your computer where you want to store your audio files (such as on a portable firewire drive).

Then select the following session options:

• Audio File Type - aiff
• Sample Rate - 44.1 kHz (unless you're planning to use the audio in a video clip, in which cae choose 48 kHz, which is the standard for audio used in video)
• Bit Depth - 16 bit
• I/O Settings - stereo mix

Then click on the Save button to save your work.

And keep saving regularly by clicking on File...Save (or use the Apple shortcut for saving - Cmd-S), so you don't lose any of your work if the computer crashes.

If you make a mistake, you can undo it by selecting Edit...Undo (or use the Apple shortcut for undoing - Cmd-Z). ProTools allows you to go back multiple steps and undo them.