There are two different methods, with different pros and cons.
Method 1 - Insertion from the gallery
The gallery is generally the best place to store and display pictures because they can be organised, annotated, searched, commented and rated when in the gallery. The home page pictures are also taken only from the gallery. Nonetheless it's sometimes convenient and make sense to include pictures in your forum posting. This method allows multiple pictures to be posted together.
See this article for step-by-step instructions:
How to insert gallery pictures into articles or forum postings
Example (click to enlarge):
{jwpics 6,7;2;1}
Method 2 - Direct file upload / insertion into posting
For pictures that are of limited interest outside of your forum posting, for example, pictures of goods for sale, advertising images and such like, it's better to upload and insert them directly into the posting. Note that the file size limits are smaller for this method. You can include only one picture per posting by this method.
1. Put the cursor where you'd like the image to appear.
2. Browse for your image file in the "select image file to attach" field at the bottom of the submit form.
3. Press the
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