1. Download from Microsoft website and you can use it. First, get your computer ready and make sure you are running the latest version of MAC OS X. The old version of OS X may not be compatible with the latest Microsoft office software. Make sure that your hard disk has enough space to install the software. Look at how many GB is left on the hard disk, which is 20% more than the remaining space on your normal hard disk.

2. Go to the Microsoft website.

3. Click the "Buy Now" button in the upper right corner.

4. Choose a different version. The home edition and the student edition don't allow you to use it for commercial purposes, but the home edition and the enterprise edition can.

5. Click "Buy Now" again. Click the button next to the version you want to buy.

6. Fill in your information. Browse all the text fields and fill in your personal and payment information so that Microsoft can make a transaction.

7. Click "Continue". Follow the prompts and you can download and use Microsoft office software.

8. After downloading, you can use Microsoft office software.