The method is as follows:

1. After creating a DingTalk group chat, click the smart group assistant in the group settings in the upper right corner.

2. Select a custom robot on the robot management page, enter the robot name and select the group to send messages to. You can also set a robot avatar for the robot.

3. Check to add a signature, check I have read and agree to the "Custom Robot Service and Disclaimer", and then click Finish.