There are two things you need to do to get started: (1) put all the images you want in your slide show into a collection, and then (2) go to the Template Browser panel (in the Slideshow module’s left side Panels area) and click on one of the predesigned templates as your starting place (as you hover your cursor over any template, a preview of that slide show layout appears in the Preview panel, at the top of the left side Panels area). I say “starting place” because none of them are particularly good looking (take the one above for example, Caption and Rating, which displays a star rating over the photo and your caption underneath, right at the edge of the slide. What a stunning layout). Okay, trying not to get snarky here, but the templates, which shipped with Lightroom 1.0 (about eight years ago and haven’t really been updated since), might be due for a refresh, and that’s being incredibly kind. But, like I said, it’s a starting place, so choose the one that looks the closest to something you might actually want to use. Also, once you’ve got your template in place, go to the Playback panel (at the bottom of the right side Panels area) and click the Automatic button, if you plan on creating a self-running slide show (one that advances through the slides automatically). You’ll also see options here for background music, and transitions and movement, which you’ll probably want in the slide show. The other choice, Manual, is for when the slides only advance when you press the Left and Right Arrow keys on your keyboard (ideal if you’re telling a story and want to move through the slides at your own pace).