SSH into my server and update file ownerships

I am really just trying to change two banners on my site but I host with The Planet and the freelancer I hired to do that had difficulties because he was unable to do it simply through FTP. Apparently, I need to SSH into my server and update the file ownerships so that we can get access to change those two banners. Here is what i got back from my host, with regards to the Chown command. If you can help me get this done then bid on this project and help me change these two banners tonight! As FTP using the bdsmplay user, it doesn't have permissions to overwrite root owned files. You may change the permissions on files with the chown command. This link offers detail on the chown comand: [login to view URL]