This article explains how to set up a HomePod Mini.

The HomePod Mini has limited physical controls and no display, so you'll set it up using an iPhone, iPod touch, or iPad. The device will need to be signed in to your Apple ID account, connected to iCloud, connected to the same Wi-Fi network you plan to use with your HomePod Mini, and have Bluetooth enabled.

Here's how to set up a HomePod Mini:

Connect HomePod Mini using the included power adapter or another compatible USB power source and wait for it to turn on.