Pink chinos. These are bold summer pants. There is no way around it. The easiest, simplest path would be a brown belt and white OCBD. Today, in the late summer, I felt it appropriate to go "all out". All out (within reason) in this scenario means an aqua (very subtle aqua almost blue, essentially just a very summery blue) university stripe and a green patchwork madras belt. When you push everything this hard, a tie isn't going to happen. To try to incorporate a tie with an outfit like this would be too much. It would crowd everything else and would draw your eye in too many places.
Interestingly enough, I may suggest that it is easier to pull off the aqua university stripe and green madras belt with the pink chinos than it would be to pull off even a simple tie with a brown belt, white OCBD and pink chinos. It is hard to describe, but it feels that way. A tie inherently feels very put together, very intentional. The belt can give the sense that it was an afterthought, a throwing caution to the wind bit of fun. The shirt fills in the spot of a garment on our chest, it is the garment we wear every day. To try to pull off a tie with pink chinos may feel as though the outfit is entirely "put on". It could feel too "intentional", and not in a good way. Yet, it could also go the other way. In its boldness it could evoke a carefree attitude. It could go either way and depends ultimately on what one individual can pull off. A very precarious pair of pants to wear when venturing beyond the most basic (and beautiful), clear choice of a brown belt and white OCBD.