Which would be the best collages for fashion designing?

It totally depends on a number of factors:

1. What do you want to study: fashion design, fashion marketing, fashion media, fashion business, luxury brand management, etc?
2. Are you looking for a Bachelor degree or a Master/MBA degree? Perhaps professional training in form of a short course?
3. Which region are you looking at? There are great schools all over the world. Cities like NYC, London, Paris have a lot of great fashion schools.
4. What is your budget? Fashion schools can be quite pricey, up to $50,000 per year.

If you tell me the above, I can recommend you a suitable school.