Dressing for success is about dressing well. The basic rule in feng shui is to avoid clothes that are torn, old or make you look like a homeless individual.
There is a custom among the Chinese nation (one of many) that every Chinese New Year they buy new clothes because they want to start the New Year with new, auspicious energy.
Even better, of course if you can afford, is to shop for new clothes every season.
For all you ladies, that is a very good excuse!!!

As for colours in feng shui there are few methods you can use.
The easiest is to check your KUA number. Depending on your KUA, different colours mean different things & they bring different kind of effects.

In the chart below you can check which colour is responsible for what.
But please do not go overboard and look stereotyped (see below for assistance).