> For the complete documentation index, see [llms.txt](https://docs.tonic.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tonic.ai/textual/entity-types/entity-type-custom-model/model-entity-type-new.md).
# Starting a new model-based type
To start a new custom entity type:
1. On the **Additional Entity Types** page, click **Add Custom Entity Type.**
2. On the **Add Custom Entity Type** panel, click **Model-based**, then click **Next**.
Panel to select the type of custom entity type to create
2. On the next panel, in the **Custom entity type name** field, provide a name for the custom entity type.
3. In the **Annotation guidelines** text area, provide instructions for how the model should identify values that you want to find. This is the first version of the model guidelines.
Panel to provide the name and initial guidelines for a model-based custom entity type
4. Click **Next**.
Textual displays the **Test data setup** page.
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