Probably this could help!
https://www.physicsforums.com/insights/geometrical-view-time-dilation-twin-paradox/
The answer lies straight down in the last diagram.
Hey there!
This is Mayank Bhandare, from India. I am a recent graduate in Mechanical Engineering from the University of Mumbai. Though it's a strange switch as many would say, I am planning to pursue a career as a Theoretical Physicist/Cosmologist. I have a couple of entrances the next month...