For a devotee death opens door for liberation but for a non-devotee death is end of everything.
To serve Krishna means life and to engage in sense gratification means death.
Thinking of Krishna is not based on your concoction. If you are Krishna Conscious and pure in your life, Krishna will reveal Himself as the last thought at the time of death.
One should leave the body in the presence of vaishnavas or alone, but not in between whole family and friends.
Shravanam, Kirtanam, Smaranam. Kirtaniya sada hari. Constantly remember. So, at the time of death, we will be able to glorify the Lord.
For a devotee death is not the end but just the beginning. Beginning of entrance into a realm of eternity.