https://steemit.chat -- login. It is a basic chat program. In the upper left corner there is a search bar...

start typing steemcleaners-linkdrop -- click on the link and it will say you are in preview of the channel. Click Join (gray button near bottom of the screen).

A box will appear at the bottom. This is where you type your words (not a long paragraph. just a quick blurb about the abuse found -- tag spam or stolen content).