I normally just copy/paste or drag an image from my desktop to the content area of my post. If the image is too large, I click on the image and drag it smaller from the edge.
For those who would like more options, see the tutorial below.
How To Upload Images To Posts
Start your post and normal and then click on the insert image icon.
It will pop up telling you to drag an image there or click. If you drag and drop it, you will see it show up in your post. If you click, it will allow you to navigate to where it is on your computer.
Then just click the image so it adds the file name for you, then click on open.
Finish adding any content and then simply post your reply.
- Cricket