What mindfulness practices suit my cousin to reduce worry and overthinking per his chart?

My cousin has been stressed out lately. He worries so much — about studies, about what other people think, even about little things that don't really count in the long term. I can see his mind does not like to turn off at all; he's always overthinking something. I started to think that I could use astrology to help determine what kinds of mindfulness practices might suit him. Perhaps his chart presented some planetary aspects — like a busy Mercury or a sensitive Moon — that made him prone to worry. I wondered if gentle breathing exercises, journaling, or grounding meditations could contribute to Rohan’s sense of calm from thinking.