Attitude is everything, both in style and in life. Start your personal style journey every day by thinking about who you are and what you represent, yourself, family, business and values. Caring about those things strongly makes me care strongly about how I present myself. I give a damn.
You need to have a little understanding of fashion histories, such as where modern styles came from as a philosophical and a practical consideration. If you just try to memorize “do and don’t” rules, it gets overwhelming. There’s too much to handle, but, don’t be afraid to lead. Do not be afraid to be the best-dressed person in the room.
Dressing doesn’t have a lot of fixed yes-or-no rules, and the few that it does have can be broken stylishly (and have been), but you need to know what you’re doing, and why. Otherwise you just end up not looking great.
Plain and simple, a good fit should flatter your body. It will draw attention to the parts of you that you want and it can also minimize aspects you’re not as fond of (a large midsection, for example). Take the time to get to know your body, and have a tailor help you get accurate measurements. Learn to say “no” to clothes with a style you like, but a fit that can’t be adjusted to suit you. It really does matter.
A good dresser keeps his environment in mind — both the physical and the social aspects of it. Physically, you want to be comfortable. That means lighter clothes in warm weather, thicker layers in cold, and a good fit all the time. Changing your wardrobe seasonally adds a little expense when you’re first building it, but over time you’ll end up saving wear and tear (and sweat damage) as you spread your usage out over more weather-appropriate options.
Socially, you want to look respectable at all times, and make the effort to fit in while looking sharp.