Short answerA polo should skim rather than cling, an Oxford shirt should close comfortably without billowing, and chinos should sit cleanly through the seat and thigh with a controlled taper. In all three, movement should remain comfortable and excess fabric should be limited.

The two-minute fitting-room test

Stand naturally, sit, reach forward and raise both arms. The garment should return close to its original position without cutting into the body or remaining badly displaced. Judge the front, side and back; a mirror from only one angle hides many fit problems.

The knit polo

The shoulder seam should finish near the shoulder point and the sleeve should sit around mid-bicep without squeezing. The body should follow the torso with a little air, not pull into horizontal lines. The hem should usually land around mid-fly so it works untucked and does not expose the stomach when reaching.

The Oxford shirt

You should be able to close the collar comfortably, even if you usually wear it open. Look for a clean chest without pulling at the buttons and enough room to reach forward. At the waist, avoid both tightness and large folds of excess fabric. The cuff should finish near the wrist bone; the shirt tail must stay controlled when tucked.

The chinos

The waistband should stay in place without a belt but never dig in when sitting. Pockets should lie flat. Fabric should fall cleanly from the seat through the thigh, then taper gradually. A slight break or no break looks modern and controlled; heavy stacking usually makes the leg appear shorter.

Alter or change size?

Sleeve and trouser length, a modest waist adjustment and some shirt shaping are common alterations. Shoulder width, a very tight seat, extreme pocket flare and a low armhole are harder to fix economically. If the structure is wrong, try another size or cut rather than forcing the garment.

The final question

Ask whether the garment makes the rest of your wardrobe easier. Good fit is necessary, but the colour, texture and formality still need to work with several items you already own.