How could I add attachments to a post?

[Nathan Ross]

After uploading, I click on "add attachment", but then it disappears.

After clicking 'add attachment' there's an extra stage to the process! You'll see another button has appeared in the 'attachments' box called 'Insert into Post' - if you click on this one the image will be added to your post, wherever you have placed your cursor.

Hopefully that should work!