Connection of the junction box for the 3-way switch with the cable from the first 3-way switch and the cable to the light outlet.
Details on wire splicing and connecting the switch.



Disclaimer.
This video show 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!