how do I know the source/ referrer of how members are signing up to my site?

Hi Kazmatic,

To check anything related to your traffic, feel free to go to "my sites", then "manage" next to the site you need to check, and "traffic statistics".

From here, you will have access to numerous statistics, including the following:

When: Summary Days of month Days of week Hours
Who: Countries Hosts Domains Robots/Spiders visitors
Navigation: Visits Duration Files type Viewed Entry Exit Browsers Browsers(versioned) Operating Systems
Referer: Search Engines Links from external pages Search Keyphrases Search Keywords
Other: HTTP Status Codes Pages not found

Hope this helps!