unfortunately it is impossible to protect yourself completely. a small © in the lower right corner, or left corner/sides if its too distracting in the BR.
did you know the act of cropping the © notice is a crime in itself...circumnavigating copyright protection measures. it also almost proves they knew what they were doing was wrong and still did it...makes for more $ if it goes to court.
on my site.
www.shutterworksphoto.com i keep all my images to 500p on the long side, i have a © warning box on my home page thats a bit detailed but just a few lines and under each image in my portfolio i have © (photog name)
i have seen websites that when you click on the portfolio page it redirects to another full page with © notice info, then it has enter portfolio button on the bottom...very annoying.
a local portrait studio heavily watermarks their proofs. they type over ALL the image, ©(Studio) professional photo, do not copy (and repeats this over), lines of text probably appear 5-8 times on a proof with that phrase repeated.
and i have heard stories of people printing a proof with the proof waterwmark across the center and framing it and putting in in their living room on a coffee table/