Put On Quality Footwear
Good quality shoes speak a lot. Avoid multicolored sneakers with crazy designs that stand out in a horrible way. While you build a fashion sense you are comfortable in, stick to mono-chromatic or solid colors preferable of a dark shade. Get a pair of loafers or open toe sandals if you live in a warm country. Make sure to have a pair of black causal shoes whether sneakers or otherwise since black can be worn with just about any color.
Wear quality clothes
Make sure that the cloth you have on is of good quality. This means it should not be torn or have that worn out look. It does not have to be expensive clothes but with a good eye you can spot quality at a low cost. Stock up on a few shirts long sleeves, short sleeves it does not really matter. Go for plain colors like a light blue, black, brown or cream for example. Patterned shirts need a subtler touch so hold on till you get a grip on this whole casual wear. T-shirts are the ultimate causal wear, so stock up on those too. These can be paired with a good pair of jeans. Make sure your shirts are firm, with needle-work and that they hang a bit loose on your frame. Do not wear dress shirts (which are always longer that regular shirts) without tucking them in
Whether it’s a solid watch, a hand bracelet, a loosen tie or cravat, a handkerchief or even a man-purse or sexy carry-able satchel with a shoulder strap even, have a subtle accessory on you. If you can, sure it matches somehow with the shoes you have on or play it classic with dark colors.
Wear the right type of jeans
Before you could only get jeans in a solid blue color, the original blue denim. In today's world, jeans variety has exploded in every respect possible from color, texture to fitting. Consider your body type before you go to purchase just any jeans, consult with a friendly salesperson to get an idea of what works best for you. Avoid bleached jeans, stained jeans and other crazy jeans for smart casual dressing. Those jeans are best suited for strictly casual interactions.
Wear clean underwear
Wear ankles or full-length socks it does not really matter, just make sure they fit well and do not sag into your shoes. Have your under shirts clean always. Do not wear a colored under shirt when you have a white shirt on.
If you sweat a lot, find antiperspirant deodorant to make sure sweat does not seep into your shirt. Make sure you smell good and your grooming is on point. If you are going to expose any part of your body like your arms for example if you are going to roll your long sleeves. Apply body lotion.