When picking out clothing for hiking, keep three things in mind.
* First, your clothes should resist wear and abrasion. Let's face it; hiking and trekking is hard on clothing, so buy fabrics that wear well.
* Second, buy clothing you won't mind replacing when it wears out.
* Third, avoid hiking clothes that are overly flamboyant.
Especially if you are trekking in an area with a conservative culture on your adventure vacation, dressing too loudly can cause friction with locals. Of course, bright colors are important for visibility, but keep local attitudes in mind when selecting hiking clothes.