How to write your first song

I watched a television contest yesterday and I am sorry to say that I can't remember any of the six songs they played -

How to write a song?

Type this question into Google and you'll find hundreds advisors. My hints are short.

Let us write a 16 bars song. Take 3 chords and build a group of 4 bars:
Example: C G F C

Now repeat this group 4 times. We call these 4 groups a verse.
Find a melody, listening to the loop.
Now it comes to invite a variation.
Use group no. 3 or group no.4.

The simplest variation could be "tacet only". Don't play chords.
Good for group no. 3. Use your guitar's body as a drum.
Change the melody in this group.

With the new melody in these 4 bars replace the tacets with new chords. There are hundreds of possible variations.

Of course you can directly create a new group of 4 at bars 9 to 12.

The second variation I would mostly add is a "bridge" of 8 bars after the 2. or 3. verse. It should contain a third idea and something different.

I guess some thousands of songs are stored in my brain. Songs like "All along the watch tower" or "Waterloo".
Why can't they play songs at a contest I am able to remember?

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