Make sure you have updated your uSchema plugin to the latest version to start using simple schema item.
To create a simple schema item go to Schema Items -> Simple Schema Items -> Click Add New. You will see some commonly used schema types. Give your schema a name, select one schema item from the listed items and click publish. (I have selected Article and given it a name “blog article”, Note: name can be anything.)

After publishing the schema item the page will reload and you will be presented with properties to configure.

In this dialogue, you can configure all the available properties.
You can type fixed values or you can link to existing fields on your website.
For example, you can select link short description with an excerpt of the post or maybe to the title or even a custom field.
You can even type a fixed value for it.
You can also create fields for this information. for example, you can create a field for Author. This field will appear in the post under the schema information tab.
Configure Where to add schema
This is the last dialogue on this configuration page. Here you configure where you want this schema item to show. This option allows you to configure multiple rules for inclusion and exclusion. You can add schema to all the posts and exclude some posts based on a specific category.