This pairing of a navy and white windbreaker and dark green jeans will be a good exhibition of your expertise in menswear styling even on weekend days. A pair of casual boots will create a stylish contrast against the rest of the look. Can you see how super easy it is to look on-trend and stay comfy when colder weather arrives, all thanks to combinations like this? And if we're talking style for 30-year-old guys, this look looks cool on most gents.