How to install it:-
Log in into blogger
Click Layout.
Click Edit HTML tab
Click Download Full Template and back up the template first.
Find the code similar with the code below without expanding the widgets
<b:section class='sidebar' id='sidebar' preferred='yes'>
Now Place the below codes immediately after the above line you found
<b:widget id='Label99' locked='false' title='Labels' type='Label'>
<b:includable id='main'>
<b:if cond='data:title'>
<h2><data:title/></h2>
</b:if>
<div class='widget-content'>
<object type="application/x-shockwave-flash" data="http://halotemplates.s3.amazonaws.com/wp-cumulus-example/tagcloud.swf" width="250" height="200" allowscriptaccess="always" >
<param name="movie" value="http://halotemplates.s3.amazonaws.com/wp-cumulus-example/tagcloud.swf" />
<param name="bgcolor" value="#ffffff" />
<param name="flashvars" value="tcolor=0x000000&mode=tags&distr=true&tspeed=100&tagcloud=<tags>
<b:loop values='data:labels' var='label'>
<a expr:dir='data:blog.languageDirection' expr:href='data:label.url' style='12'><data:label.name/></a>
</b:loop>
</tags>" />
<p>Blogumulus by <a href='http://www.roytanck.com/'>Roy Tanck</a> and <a href='http://www.bloggerbuster.com'>Amanda Fazani</a></p>
</object>
</div>
<b:include name='quickedit'/>
</b:includable>
</b:widget>
Now you can Preview your template. If its Ok You can Save it.
You can change codes highlited in red above to change the color of text in blogumus and background color of it.You can also alter its size to adjust your sidebar just edit the red values in above codes.
I hope you will insall this widget succesfully. If you have any problem in insatlling it you can read this tutorial from Amanda too.