For pages that have an image gallery, simply upload your image to that page using [Attach]. There is no need to create a link to the image on the page.
If you have many images to upload, use an FTP (File Transfer Protocol) program to upload all the images at one time to the 'pub' directory related to that topic. For example, if you want to attach to ExampleTopic in Sampleweb, then the directory will be:
Just click the first image to be able to view the images in a convenient slideshow format. Click the image again for a high-resolution version. Click > or < to move forward or back in the set.
If you have any difficulty with viewing, try using a browser based on Mozilla, such as Firefox, which you can download for free here: Download