Please follow these directions to install Steam on a Mac (email firstname.lastname@example.org if you have questions):
- In a web browser, go to http://store.steampowered.com/about/
- Click the Install Steam Now button or link appropriate to your operating system.
- The web browser will ask you what you want to do with a file named Steam.dmg. What you should do is save the file to your computer. Make sure that you remember where you save it!
- Run the Steam.dmg file that you just saved.
- Accept the License Agreement.
- Drag the Steam icon into the Applications folder.
- Done! Steam is now installed on your computer.