When you launch the Browsealoud Toolbar you will normally see all the features as in the screenshot below, including the Translation feature, which is in blue.
If you launch the Browsealoud Toolbar and you do not see the Translate feature, (as below) this could be due to the site being secure (https). The Translation will not work over a secure site as we have to send the text to our translation servers to be translated, and if the site is secure you are not allowed to do this with secure content.
You can check if the site is secure by looking at the URL in the address bar at the top of the page, if it says https like below the site is secure.
Also please note that Translation may also be disabled by the site owner, meaning the button will not appear.