This is based on a list from “Eric the Black”, a professional through (very long distance) hiker , defining the minimum necessary gear.  He lists recommended brands of items from his experience on his web site (http://blackwoodspress.com/blog/2157/backpacking-clothing-system/).  However, you should be able to fill this from items you already own.

This is all you need for a weekend backpacking trip!

Clothing to Wear

• Polyester or micro-weight merino wool boxer briefs
• Polyester or micro-weight merino wool T shirt
• Polyester or micro-weight merino wool hiking socks (over ankle)
• Lightweight running style shorts (or shorts from zip off pants)
• Lightweight ball cap
• Sunglasses
• Watch
• Mid height or low hiking boots or shoes

Clothing to Pack

• Spare hiking socks
• Thermal top silk weight (silk or lightweight polyester like under armor) for cold mornings and sleeping
• Thermal Pants silk weight (silk or polyester) for cold mornings and sleeping
• Insulation Layer (fleece jacket or puffy vest)
• Rain Jacket
• Rain or wind and water resistant pants (or legs of zip off pants treated with DWR)
• Sleeping socks (fleece or wool)
• Hiking Gloves (stretch lightweight poly or wool liners)
• Beanie hat (micro weight fleece or wool) for cold mornings and sleeping

How to Pack a Backpack

From Eric the Black’s Backpacking Blog, read “How To Pack A Lightweight Backpack”

Lightweight Backpacking Makeover Video

From Section Hiker: Hiking and Backpacking for Beginners and Experts:

Actions often speak loader than words – so here is a backpack makeover video we shot last month at a lightweight backpacking seminar we gave for boy scouts (that applies to anyone) that demonstrates the decisions that go into this process. In it, Grant Sible and Dave Cutherell from Gossamer Gear show an adult backpacker how to reduce her load from 26 pounds, without water and food, to 16 pounds.