The pattern of swimming trunks will particularly impress me as a boy, at least indicating that he dares to show his taste. After all, playing too many safety cards is boring. But it doesn't mean that solid color swimming trunks don't look good, just need more textured fabrics and exquisite details.
On the whole, solid colors are more suitable for burly boys and have visual effects. Choosing bright colors is more in line with the summer atmosphere. For slim boys, rich patterns can enlarge your figure as a whole, at least not too petty, and the whole person looks clearer.