This vibrant, multi-colored pocket square with its geometric pattern can be paired effectively with several neutral suit colors to create a stylish look.    
Navy Blue Suit: A classic navy suit works exceptionally well as it provides a sophisticated, neutral backdrop that allows the various blue, green, and orange tones in the pocket square to stand out.  
Light or Charcoal Grey Suit: Grey is a versatile neutral that complements almost any color. A light grey suit is great for spring/summer, while a charcoal grey suit offers a sleek, unobtrusive look that pairs well with the cooler tones in the square.  
Tan or Beige Suit: For a more casual, daytime, or summer look, a tan or beige suit would pair nicely with the earthier tones like the orange/peach and green in the pocket square.  
Green Suit: You could also pick up on the green in the pocket square and pair it with a forest or olive green suit for a more coordinated and intentional look.