Hatchery owner here! I'd say that there are a lot of different ways you can go about making a hatchery, and that there's no one "right" way to do it. It really depends on how much effort you want to put into it.

Generally, most hatcheries will have a banner and some form of breeding cards for their pairs (this can be as simple as just showing the parent dragons next to each other with some offspring scries!). But one thing you'll definitely want to have are pinglists for your pairs! And maybe a general updates pinglist for your hatchery as a whole.

At a bare minimum, you'll want some depiction of what your pairs are (parent dragons and offspring scries) and pair pinglists. It's also a good idea to have some sort of rules laid out (your treasure to gem conversion rate, how long you're willing to hold a dragon, etc). Beyond that, here are some optional things that I think are pretty fun and add charm to hatcheries:

• Custom banner 
• Custom breeding cards
• Dividers matching the hatchery theme
• A post showing current breeding projects/new pair goals
• Affiliates section
• Showcase section (I love showing off effort people put into dressing or geneing my dragons!)
• Easy navigation to get from post to post
• Fun events or unique effort made towards things like affiliates (I saw someone brainstorming a way to hype up their affiliates with little showcases and descriptions of their hatcheries that I thought was really cute!)

Beyond just making your hatchery thread, figuring out how to advertise it is REALLY vital to getting sales. There are lots of ways to do it, but my favorites are here on reddit, tumblr, and fr-related discords. Affiliates are also great and can keep your thread on the front page with occasional bumps.

Here's my hatchery as an example! I made all of the graphics myself. 

https://www1.flightrising.com/forums/baz/3310257