The best way is to go over the games yourself first, and then check out your analysis with an engine, going over moves and variations with the engine manually (i.e NOT using any automatic full-analysis features).
For that, you can download free GUIs like Arena or ChessDB and free engines like Firebird (the strongest engine at the moment) or Stockfish.
Sorry if this has been asked a million times. What is the best software for going over your own games and annotating the moves with comments? Where can I download this software?
I have been trying to do this with a programme that is mainly a chess engine and isn't really built for analysing your own games which makes it awkward