Among the features of GNOME 3 is an embedded screen recorder.

Link: GNOME screencast

One restriction is the fact it has a default recording duration of 30 seconds. Do not worry as we can adjust this.

Note: We will be increasing the duration to 60 minutes.

Open a terminal and enter:

gsettings set max-screencast-length 7200

For other durations greater than a minute, use formula: 60 * number_of_minutes.