Ultimate Checklist to skyrocket your YouTube CTR
The thumbnail has a maximum of 3 visual focal points (e.g., Face + Object + Text). It looks clean and doesn't clutter the viewer's sight.
I have stepped back from the screen or scaled the thumbnail down to 20%, and I can still easily understand what's happening in the image.
I used colors that break YouTube's pattern. The text and the main subject pop strongly against the background (they do not blend in).
The words generate curiosity or urgency. They DO NOT repeat the video title. There are maximum 4 words in a bold, readable font.
If a person is shown, their face displays an exaggerated emotion (surprise, fear, extreme joy, confusion) that connects with viewer psychology.