As the first step you need to add TalkingDeck as add-onto your Google Slides interface:
From that point on, you can always access TalkingDeck by opening Add-ons in the menu. Click “TalkingDeck”, followed by “Open TalkingDeck”, and the sidebar with the interface will open on right side of the screen.
There is one important requirement before you begin. TalkingDeck converts speaker notes of each slide into the narration.
You need to have speaker notes field opened. It should be visible at the bottom of your screen.
If it is not, please open the “View menu”, and click “Show Speaker notes”.
Start by creating a new presentation, or by opening one of yours.
Once you have the presentation on the screen, make sure to open the TalkingDeck interface.
You can always access TalkingDeck by opening Add-ons in the menu. Click “TalkingDeck”, followed by “Open TalkingDeck”, and the sidebar with the interface will open on right side of the screen.
Also, make sure to have the speaker notes field visible at the bottom of the screen. If they are not, please open the “View menu”, and click “Show Speaker notes”.
It is a good idea to set the dimensions of your slides equal to the final video dimensions right at the beginning. Otherwise, you will end up moving things around at the end and waste valuable time.
Keep in mind that TalkingDeck can render only static slides. Any animations, transitions and interactivity which you add to your slides will not end up in the video.
Also, maximum duration of the narration in slide is 30 seconds. This is equivalent to approximately 600 characters of text in speaker notes