Different folks, different strokes.

I would say that the equivalent phrase in Spanish would be "Cada cabeza es un mundo diferente" because it refers that people do things in different ways. differe

Let's see an example:

My classmate opened a store and doesn't promote it. I helped him to do a sales strategy but you know different folks, different strokes.

Mi compañero de clase abrió una tienda y no la promueve. Le ayudé a hacer una estrategía de ventas pero tu sabes que cada cabeza es un mundo diferente.

I told them to wear a nice outfit to attend to the weeding, but they dressed as in the picture. Different folks, different strokes.

Les dije que se pusieran un bonito conjunto para ir a la boda, pero ellos se vistieron como en la foto. Cada cabeza es un mundo diferente.