I myself use Radeon's Relive, though I usually only use it to record highlights, not the whole match. Pressing the command will record the last 3 mins since thats how long a round usually lasts, but you can change it) and automatically saves it on a folder.
I make sure that I also record my mic audio (no webcam atm) to see where I get frustrated and when.
I then use Handbrake to minimize the file size since 3 min clips can go up to 300 MB or more depending on the recording quality.
There could be other better software to record your gameplay but I just coudlnt be bothered installing another software so I'm using what comes with my Video Card.
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