The skeleton for my SoP looked like this:

• First Paragraph: Introduce myself, my research interests and what are my career goals. Schools like Stanford specifically ask for what are your expectations from your life after attending Stanford.
• Second Paragraph: How my first research internship (after second year) helped me develop my interests in the fields I mentioned before.
• Third Paragraph: How the previous internship led to a research idea which I worked on during my junior year and how things didn’t go as expected. Yes! I did mention about the failures I faced during the research project. I wanted to convey that I know what to expect from my PhD which is basically facing a lot of failures in research before making things work.
• Fourth Paragraph: The research methods I learned during my second research internship.
• Fifth Paragraph: How the research methods I learned in the previous internship helped me overcome the failures faced in the project mentioned in the third paragraph.
• Sixth Paragraph: Mentioning which labs I am interested in and which projects/research work carried out in the lab I found interesting and how it
• Seventh Paragraph: Mentioned which research problems I would like to tackle during my PhD along with a few ideas to work on. You can get to know which problems are important in your research area by going through a survey paper on that topic.
• Eighth Paragraph: Named a few profs I wanted to work with along with reasons like a particular area he/she was working on, etc.
• Ninth Paragraph: Conclude and reiterate ‘Why research instead of something else?’