Thanks to member Michael Shea for providing these instructions.

1) Click the "Image" button as shown in the picture below:

2) Select the "Upload" tab and your screen should look like this:

3) Hit the "Browse" button and select the picture you want to upload from the folder on your computer in which it is saved.  With the title of the photo now showing in the field, click "Send it to the Server".  (The gray bar shouldn't appear - I just wanted to censor personal info.)

4) It takes just a minute for your photo to be uploaded to the server and once it is, the next screen you'll see is the one below.  Follow the instructions typed next to the red arrows below.

...and that's all it takes.  The Drupal software will automatically take you to your post.

Note:  If you are embedding an image into a forum post and want the image to fill the width of the forum window, set the Width to 720 and leave the Height blank.