I go to Google Images, type in subject (such as: cat chasing dog, Trump's hair, starry sky, etc.) and you'll get a page of graphics pertaining to your subject. Click on the photo you want and it will open up in a gray/black box. To the right of the photo you will see two small boxes reading:
Visit page and
View image Click on "
View Image" and it will bring you to a page with that image only. Copy the link in the address bar, come back to CC thread and click on "Insert Image" box above. When it opens, paste the URL in the box provided. It should load onto the thread then.
Keep practicing and you'll get it. It took me a while to get the hang of it.