The Download Now link will redirect to the extension page. To install the extension directly, Open the page in Google Chrome and click on the install button on the page.
From Google Chrome extensions:
Google Input Tools lets you type in your language using the input tools familiar to you. It allows you to switch to typing in a different language with the click of the mouse, and switch back just as easily. The Google Input Tools extension provides virtual keyboards for over 70 languages, and full IMEs or direct transliteration for over 20 different scripts.
