> ## Documentation Index > Fetch the complete documentation index at: https://tyk.io/docs/llms.txt > Use this file to discover all available pages before exploring further. # Customize Sign Up Form in Developer Portal > How to customize sign up form in developer portal In this section, you will learn how to customize the sign-up form for your API Consumers and extend the data stored in the user profile. To achieve that, you will need to: * Add a new attribute to the user profile and make it available in the sign-up form. * Optionally, add a description and set other parameters that suit your requirements. ## Navigate to the Custom Attributes menu To customize the sign-up form, you need to add new data attributes to the user model so that when a user profile is being created, those attributes will be recorded against the user profile. To start customizing the user sign-up form, navigate to the **Custom attributes** menu and the select the **User** model. Currently, it is possible to extend only the user model. In future releases we will add the same capabilities to other models. Navigate to the User's attributes ## Add a new attribute to the user model To add a new attribute to the user model, click on the **Add Custom attribute** button and then fill in properties of the new attribute: * **Attribute ID**: A string that consists of letters (a-zA-Z), numbers (0-9), dashes, and underscores. This is used to reference the attribute in the [Admin APIs](/product-stack/tyk-enterprise-developer-portal/api-documentation/tyk-edp-api) screen. * **Attribute Label**: The attribute's name that is displayed in the UI. * **Description**: Explains the intended usage of this attribute. It is also displayed in the UI. * **Type of attribute**: The type of data that can be stored in this attribute. You cannot change the value of this field once the attribute is created. The following data types are acceptable: * Boolean (true or false). * Dropdown (a list of values). * String. * Number. * **Validation Reg Exp**: A regular expression that is used to validate the value of this field. It is available for the **String** data type only. * **Enable validation**: Determines if the portal should apply the regular expression defined in the **Validation Reg Exp** to validate the value of this attribute when creating or updating a user profile. It is available for the **String** data type only. * **Dropdown Values**: A list of values for the attribute. It is available for the **Dropdown** data type only. * Fields that define the attribute's behavior: * **Write once read many**: Determines if the value of the attribute can be changed after a user profile is created. * **Add to the key metadata**: Determines if the value of the attribute should be added to the metadata of Auth keys or OAuth2.0 clients when a user creates them. Keep in mind that credential-level metadata will be accessible in both the gateway runtime and gateway database. Please be cautious when handling personally identifiable information (PII) data. * **Required**: Determines if this attribute is required to create a user profile. * **Show on sign-up form**: Determines if this attribute should be visible in the sing-up form. * **Behavior**: Determines if developers can view or edit this attribute. Possible values are: * Developers can view and edit the attribute. * Developers can only view the attribute. * Developers cannot see the attribute. For the purpose of this guide, make sure to tick the **Required** and **Show on sign-up form** checkboxes and select the **Developers can only view the attribute** option. Add a new attribute to the user model The new attribute will be added to the user sign-up form, once you have created a new custom attribute and saved changes to the user model by clicking on the **Save** button. Customized user sign-up form