Tailored clothing is expensive, but the good news is that you don’t need much of it to be well dressed. Back when he wore a coat-and-tie every day to work, our friend Graeme in Sydney had seven suits that he could break into separates, and he was one of the best dressed guys around.
The key is to focus on the fit and silhouette of clothes, rather than novel details and colors. Sport coats, for example, should be kept to darker shades of blue and brown, while trousers should be lighter shades of brown and grey. Keep trousers solid colored, but get a few jackets with patterns. Doing so will allow you to combine things in an infinite number of ways without needing to put too much thought into what you want to wear in the morning.
Once you have the basics, it can be nice to branch out into more adventurous combinations. One reliable way to shake things up is to invert the traditional combination mentioned above. Instead of having a dark jacket and light colored trousers, try having a light colored jacket and dark trousers. Think: muddy browns and dark grays for pants; then dusty tans and light grays for jackets (light gray being primarily useful in tweeds).
Gustaf in Stockholm wears these kinds of combinations well. In the above, the soft, curvy sport coat is by Sartoria Corcos, a small, bespoke tailoring shop in Florence, Italy. The jacket is a summer-weight wool/ silk/ linen mix, with a faint pattern to help add visual interest. Trousers are a lightweight fresco wool, which is a nice breathable material for warmer days. The colors here are simple (still mostly relying on browns, blues, and grays), but the fit makes this outfit exceptional.
It’ll always be easier to combine darker colored jackets with lighter colored pants, but if your closet is already full of navy blazers and dark brown tweeds, it can be fun to add a little variety. Just make sure that when you’re buying a lighter colored jacket, you have at least two pairs of pants to go with it. Otherwise, you’ll effectively have a suit.