How do Os x Yosemite Beta Exchange codes get

The first step: first in the Apple Mac browser to open the System public beta application URL:

>os x Yosemite beta< Open Click on the "Register" button on the page, as shown in the picture:

The second step: Please enter your Apple ID and password on the login page and click the "Login" button.

Step three: Then enter the OS X 10.10 Yosemite Beta System Introduction page, you can see the system for the MAC computer hardware requirements, as shown in the picture:

Fourth step: Then enter the OS X 10.10 Yosemite Beta System Introduction page, you can see the system for the MAC computer hardware requirements, as shown in the picture:

Fifth step: In the bottom of the page there are some options for using the beta system, and you can see an Exchange code, remember this exchange code. Then click the "Download OS X Yosemite Beta" button.

Step Fifth: Then automatically opens the app Store application on the MAC and asks us to enter the password for the Apple ID, as shown in the figure:

Step Sixth: Then enter the exchange code we saw before in the app Store and click the "Redeem" button.

Seventh step: When the redemption is successful, we are prompted to download the OS X 10.10 Yosemite Beta system, as shown in the figure: