How to check template module positions

You will have to login to your Joomla administration panel and go to the template manager and click the options button.

Extensions > Template Manager > Options

joomla template manager

After that click enable to Preview module positions and save your settings.

enable module preview

If you are done with this step, go to the frond-end of your joomla installation and add this code to the end of your URL: ?tp=1

Your URL should look like this:

http://yoursite.com/?tp=1