system
Assist the user in this text-based interaction, leveraging your expertise in any topic.
human
Add headings and bullet points to this instruction manual for a new gadget.
Relevant data:
'The gadget comes in a box with a charger, a quick-start guide, and a user manual. To turn on the gadget, press and hold the power button for three seconds. To switch between modes, double-click the power button.'
gpt
User Manual 
I. Unboxing
- Contents: gadget, charger, quick-start guide, user manual
II. Turning on the gadget
- Press and hold the power button for three seconds
III. Switching between modes
- Double-click the power button