1. The Three Cs 

Colour
Not all colours work in business scenarios. White works well with nearly everything; if you want to add some colour, light blues and pinks are a safe bet.
 
Collar
A forward-pointing collar, or a full or half Windsor collar, are your go-to shirt collars with a tie. Also consider the shape of your features: a square face or wide neck suits pointy collars; slim faces suit a cutaway style.
 
Cuffs
These are highly visible on a business shirt, so double cuffs should always be considered first. Button cuffs are also acceptable with suits. However, double cuffs are not acceptable with mismatching jackets and trousers, or jeans.
 

2. Pattern

Pattern is acceptable on an office shirt if it is matched correctly. Choose a plain suit if you’re wearing a checked or striped shirt, and make sure the colours of your tie are complementary. A blue checked or striped shirt works well with a pink tie and vice versa. 
 

3. Fabric

The most common business shirt fabrics include poplin, twill, fine twill, herringbone, oxfords. The more texture you have in the fabric, the less formal it is.
 

4. Fit

The four most important areas for fit are: collar, sleeves, waist and length. A correctly fitted shirt allows you a full range of motion, fitting comfortably around your chest, back and armpits with no straining of buttons. If you’re a fan of a slim-fit shirt, make sure it is snug not tight. There should be no excess material around the waist and sleeve length should finish at the wrist.
 

5. Aftercare

Wash only at 30ºC to ensure no shrinkage. Iron using starch spray for increased crispness. Make sure to iron as thoroughly as you can – not just the front and back. Press an open collar and then repress the collar as you wish to see the crease, creating creases down the sleeves and shoulders. Dry cleaning is, of course, an option for the lazy launderer.