Good suits in business style — dark colors with fairly restrained patterning or texture. White dress shirts (plain or lightly patterned) and some good silk neckties and pocket squares. Oxford dress shoes and matching belts.
A good variety of trouser and jacket styles, with some lightly-patterned or light-colored dress shirts to complete the outfits. Casual leather shoes. Pocket squares for the jackets. Sweaters can work into the look too.
Clean, damage-free jeans or sturdy cotton trousers. Soft collared shirts like polos or work shirts. Leather work boots (or plain, dark-colored synthetic ones if leather isn't a viable option).
Almost anything neat and well-fitted. Sweaters, jackets, and light coats for top layers. Casual dress shirts or solid, dark-colored T-shirts, henleys, and other relaxed styles. Trousers in a variety of styles (jeans are fine, but keep them dark and fitted). Casual leather shoes.
Conservative business dress. Plain collared shirts with khakis or other “bland” dress-casual trousers. Gym shoes or other colored rubber/cloth footwear. T-shirts with logos, school or brand names, or other non-artistic graphics.
Dark, fitted trousers and jackets. Light-colored collared shirts (white with light patterning works well). Nice leather shoes and matching belts. Some modest jewelry if it's your thing. A splash of decent cologne (nothing cheap, and no more than a dab on the back of the neck).