Click on Explore > Presentations to see the list of available presentations and the public presentations. You must be logged in to see your presentations.
Click on the title of the presentation you want to create a link to. The presentation will open in the playback mode.
Click on Share This and copy and paste the URL into an email, for example.
When the user you shared this URL with clicks on the link, the presentation will open for them also in the playback mode. The aspect ratio of the images will be maintained allowing you to share the exact same layout regardless of what screen resolution the other person has.
The links you create in LUNA are dynamic, so if you make changes to a presentation these changes will also be reflected when a user launches the URL to that presentation.
Linking to a Slide:
While creating a presentation in LUNA you can easily create a link to a slide. If you have restricted content in the slide you are sharing, then users will be notified that they might not have access to all images in the slide: