4 inch round shallow ceiling light box installation in closed ceiling

4 inch round shallow "pancake" ceiling light box installation in closed ceiling.
Disclaimer.
This video shows wiring of the part of the house for "handy" homeowners who wants to perform house improvement by themselves.
This video is based on years of practice as an electrician and also on best of my knowledge of the National Electrical Code (NEC).
I do not take responsibility for any misinterpretation of the video, and any mishaps during and after work done based on this video.
If you feel any discomfort to perform DIY job, call the professionals.
Remember that ELECTRICITY IS DANGEROUS!
Any accidental touching of any live parts of the circuit may cause electric shock which may be fatal!
Always de-energized circuits before work on it, if it is possible!
Always follow national, state and local codes.