The correct way:
Connect the white of the powered cable to the neutral of the light fixture. The latter wire should be ultimately connected to the shell of the lamp socket.
Connect the black of the unpowered cable to the hot lead of the light fixture.
Connect the other two wires up in the ceiling together.
Put a band of black tape on each end of a white wire attached to a black wire or attached to a switch terminal.
Down near the floor it does not make any difference other than for appearance's sake, whether the ground hole of receptacles is up or down.
Connect the white of the powered cable to the neutral of the light fixture. The latter wire should be ultimately connected to the shell of the lamp socket.
Connect the black of the unpowered cable to the hot lead of the light fixture.
Connect the other two wires up in the ceiling together.
Put a band of black tape on each end of a white wire attached to a black wire or attached to a switch terminal.
Down near the floor it does not make any difference other than for appearance's sake, whether the ground hole of receptacles is up or down.