The unique shape of some mice can prevent them from laying flat. If you need to, lay your mouse on a soft towel to prevent wobble.

If you're planning to reuse your existing mouse feet, note that the adhesive needs to be thoroughly heated for them to be cleanly removed.

Alternatively, you can use a hair dryer to soften the mouse feet adhesive.

The information sticker adhesive may soften during this step, but you don't need to remove it.