Customizable watch faces are an integral part of the smartwatch experience. What good is a digital display if you're not going to use it to make your watch look exactly like you want it to? That's why there are hundreds of designers making faces for every wearable platform, and apps such as Pujie Black that let you create your own. The popular app was previously restricted to Wear OS but is now also compatible with Tizen OS, namely Samsung's Galaxy Watch, Watch Active, and Gear Sport. Support for the Gear S3 is coming soon.
The app isn't standalone on your watch, so you need the Pujie Black Android app installed on your phone first. When you see all the granular controls it offers, you'll understand why it wouldn't work well if it was limited to the tiny display on your wrist. After getting the app on your phone, you should grab the watch companion app from the Galaxy Store.
Then use one of the presets, create your own watch face from scratch, grab a design from FaceRepo, or use Pujie's cloud library, to get a look that suits you and send it to your watch. You can triple tap the watch display to access a few configuration options.
Pujie Black costs $2 on Android, and the watch companion app is free. The cloud library is a paid subscription, but you only really need it if you don't like your own designs or the ones you can find on FaceRepo. My past experience with the app on Wear OS has always been positive thanks to the incredible amount of options that cover everything from ticmarks to backgrounds, colors, fonts, shadows, and more, so I suggest you give it a go if you're a fan of customization. Here's a friendly warning though: Prepare to lose hours browsing others' designs and changing elements in them to fit your taste. It's a crazy time sink.