Once you have clicked on the comment box in the bottom left you will see a icon,to upload an image click it and choose your file.
Too link an image just insert the images Url,and submit the comment when done(it will appear once you reload the page)
For article Posting
When making a photo gallery
Nextgen gallery:When in the Dashboard page,find the gallery tab on the left.Choose it,select “Upload Pictures” Select your files and choose a gallery,or create one(do before choosing images)
In order to insert a gallery into your article go to the “edit” page and select the visual tab near the far right of the tab section you will see what looks like 2 squares,when you hover over it ,it will say “Add next gen gallery” choose it and select the gallery you want to insert and the form for it.
Uploading image by URL(best for few pictures)
Step 1.Find your image and load it too a reliable image hosting service.
Step 2.Go to the edit
Step 3. Above the main text box in the edit page right above the top left corner you will see two buttons by some text that says “Upload/Insert” choose the first button.
Step4.From there choose the “From Url” tab
Step 5.If necessary reduce the size of the image so that it will fit in the article with no problems.
If you have any more questions,please ask.