Here are some tips on how to write PPDT stories:

1. Observe the picture carefully: Take a good look at the picture and try to understand the scene and the characters present in it. This will help you to create a logical and coherent story.
2. Create a plot: Use your imagination and create an interesting plot that is based on the picture. The plot should be engaging and should include a problem or conflict that needs to be resolved.
3. Focus on the characters: The characters in the picture should be the central focus of your story. Try to give them personalities, motivations, and emotions that are relevant to the plot.
4. Write a clear and concise story: Your story should be clear, concise, and well-structured. Make sure that your sentences are grammatically correct and easy to understand.
5. Use the given time effectively: You will have only four minutes to write your story, so use the time effectively. Make a rough plan of your story in the first minute and then write it down in the remaining time.
6. Stick to the theme: The story should be related to the theme of the picture. Make sure that your story is relevant and has a logical connection to the picture.
7. Showcase your strengths: Try to showcase your strengths in your story. This could be your creativity, communication skills, or ability to think on your feet.

By following these tips, you can write a compelling PPDT story that showcases your skills and improves your chances of selection in the SSB interview.