When you see a topic or a comment you think needs to be reported, click the three dots on the bottom right of a post, and click on "Flag":
 

Why should a post be reported? 
If it contains any of the following:
- Spam
 - Advertisement
 - Soliciting
 - Harassment
 - Private information (Email address, phone number, etc.)
 - Any other content which is in conflict with our Terms & Conditions.
 
If you’re uncertain whether or not you should report a topic or a comment, flag it so a Moderator can review it as soon as possible and will decide further steps, if necessary.