Are you asking how to include pictures in your post?

If so;

1) upload your "reasonably sized photo" to a hosting site like Flickr, Picasa, etc.

2) determine the URL for the photo on the hosting site (they usually give you an option to share it in email, a blog, website etc.)

3) include the following code in your post:

NOTE: the red text is a tag and is required AND http://this.is.the.URL.for.your.code.html is just for explanation - use your actual URL link to your photo.