Installing the bookmarklet for Twitter Symbols is very simple, you just drag the next bookmarklet to your favorite bar if you browse is Firefox, Safari or Chrome, or add to your favorites with the right mouse click if you use Explorer:
Twitter Symbols
The way you use the bookmarklet is similar to the website. After logging in Twitter, you can tweet from the comfort of the window that appears. If you have already previously logged in Twitter Symbols and the session has not expired, you do not need is logged again.