Think about your essentials that you can wear as a base with anything. It keeps your wardrobe slimmer when you choose pieces that can be worn with a variety of different outfits, then mix it up with the right accessories (watch, tie, hat, glasses, bag).
Prints and Patterns will continue to be huge for 2015, but consider textures as well. It gives a more solid feel and makes layering much more natural. Don’t go over the top though, whilst subtle clashes can work you don’t want to look like you grands dog just threw up on you.