Take frequent breaks while using Cardboard. If you experience nausea, discomfort, eye strain, or disorientation, immediately discontinue using Cardboard.
Cardboard is not for use by children without adult supervision.
Do not use Cardboard while driving, walking, or otherwise by being distracted from real world situations that prevent you from obeying traffic or safety laws. Do not drive or operate heavy machinery immediately after using Cardboard if you feel impaired or disoriented.
If you have had or could be prone to seizures, consult a doctor before using Cardboard.