Having a tag cloud on your frontpage can be useful for users who wish to find content regarding a specific keyword. The size of the keyword in the tag cloud depends on the amount of content that is tagged with that specific keyword. So a tag cloud might look something like this on your frontpage.

Clicking on a tag in the cloud will display a list of the content with that particular keyword.
To add a Tag cloud to your frontpage, log in to the eZ Flow front-end editing interface to edit the frontpage. Select a zone and choose Tag cloud in the Block drop-down-list.

The following block will be added to the block list, where you are able to name the block if you have not done this in the previous step. Next choose a source to limit the location where tags should be fetched.

Click "Send for publishing" to complete the procedure.