from your browser go to this page: http://t13n.googlecode.com/svn/trunk/blet/docs/help.html

then scroll down on the page to where it says "Type in Nepali" Right click this link and Bookmark this link.

Next time you are on facebook or email and you want to type in Nepali, go to your bookmarks and click on this new bookmark you created and you will be able to type in Nepali