Just for reference, here's what I do using imgur:
Open Windows Explorer and navigate to the folder where the image I want to post is saved.
Navigate a web browser to https://www.imgur.com
Click on the New Post.
Where is shows Drop Images Here, click and hold on the image in Windows Explorer. Drag it to the Drop Images Here space on the web page
After you see the Upload Complete (above the new image), right-click on the image and select View Image.
Copy the address in the address bar of the browser and paste it into the Image Tool here in the forums.