To add fonts that you have downloaded, open the Fonts folder in your computer’s Documents and Settings folder. There you will find a variety of font files, including both typesface files and font family files. To add a new font, select the file you want to add and then click on the Add button.
To add a font to Illustrator cs6, first, open the “Fonts” panel and click on the “New Font” button. Then, enter the name of the font you want to add into the “Name” field and click on the “Add Font” button.