The platform you should use to create your tap essay is available at https://readtapestry.com/. Set an account up there, and give it a try.
I also highly recommend that you take a look at Robin Sloan’s Fish, which is the essay that inspired the team at Tapestry to create their software. There are lots of other examples available at Tapestry, some of which are really interesting. Explore that site if you need some ideas about how to proceed.
Tapestry is also an iPhone/iPad app–if you want to look at examples on your mobile device (including your own), you can download it. The mobile version doesn’t provide composing tools, however. That has to be done on the web.
I’ll be adding a couple of resources to this page as we go. The first tip I have for you is that the dimensions of the Tapestry “screen” are 1136 pixels wide and 640 pixels high. If you want to create a graphic in Photoshop to fill your screen, it’ll need to be that big.
When choosing color, it may be easier to use the “hexadecimal” value for the color you want (this will help you match it in Photoshop as well if you need to). Here’s a list of common colors expressed as hexadecimal values. The value is the 6 digits that follow the number sign. When you choose the color picker in Tapestry, you can input this value. There are also some really good discussions online of color combinations and the moods that they evoke.
Garr Reynolds is the author of a book called Presentation Zen. Here’s a link to a SlideShare presentation that has a lot of good before-and-after applications of his advice. His site (presentationzen.com) is full of great advice which includes slide design; here’s a post where he explains the sorts of transformations that he has in mind. He advocates for bold images, strong visual composition, and minimal text, which is good advice for your tap essays as well. (He draws on Japanese traditions as well as classical principles in his discussions of design.)
Tapestry requires a tap to move from one slide to another. If you want to add an internal pause to your slide, to require an extra tap, use the “pause button” to insert it. It will look like a circle with an x in it.
Tapestry lets you “save” an essay, which you should always do. Once saved, you can embed it on a webpage. Choosing “publish” makes it public within Tapestry, accessible to other users of the app. You can publish your tap essay or not, as you choose, but don’t do so until it’s complete.
Tapestry’s editor is very “bare bones”–to get your text spaced the way you want it, you may need to use the space bar, particularly if you want to put lines in between lines of text. There’s no easy way to do font variations within Tapestry, either. If you want a different font for a slide, you should use Photoshop to create that slide. In Tapestry, changing the font on one slide changes it for all of them.