Yeah, I know how to do it. However, I should first mention that you don't really need to use the pgnscid utility program. All you need to do is to first create a new, empty Scid database, then just import the PGN file into the Scid database.
If you do want to use the pgnscid utility, then you should put the PGN file in the same folder as the pgnscid.exe file (It's in the Scid "bin" folder) and execute the pgnscid.exe program via the command line.
If you've pointed the command line to that folder so you don't have to worry about file paths, then you only need to type:
pgnscid.exe Sample.pgn
(I guess you could just type: pgnscid Sample.pgn)
Does anyone know how to use command line utility "pgnscid" in Scid vs PC to convert PGN files into Scid database format? Do I have to open DOS window and type "pgnscid [filename]"? What directory should I be in?