Some things that you need to consider while buying underwear:

Fit

There are various styles because we have various preferences. Briefs are comfortable if you wish to have a snug fit, and trunks give better courage and comfort, whereas boxer briefs are a fusion of a fit like briefs & coverage like boxers.

Fabric

The underwear comes in all kinds of fabric, from cotton to spandex; look out for a breathable fabric that is absorbent and dries quicker, prevents bacterial growth, and is softer to your skin. Comfort is paramount.

Lifestyle

Choose a style that fits what you do, if you prefer casual clothing, briefs, trunks for formal pants & trousers, boxer briefs for a sporty fit, and boxers to lounge.