Pack It In Tight
There are three main methods that Pack-A-Pack recommends for compressing the items in your backpack: zipper seal plastic bags, stuff/compression sack, and cordage. With these three items, you can compress just about any soft item in your backpack.
Plastic Bags
Plastic zipper bags are great. You can fit clothing articles, fire starting equipment, GPS, etc. into these and use your own body weight to compress air out, zip them up, and store you items. It's as simple as that. A single 2 gallon bag can hold a days’ worth of clothing, and there is no need for labeling, as the bags are usually clear.
Stuff/Compression Sack
A stuff sack, or compression sack, is a large bag with an opening on the top that folds over the entire opening. Around the bag are straps and buckles that allow you to pull them tight around the bag, compressing everything inside. These are usually found with larger items such as sleeping bags. This usually ends up with a bulky finished item, so it's best for items at the bottom of the backpack.
Cordage
Using cordage to bind your stuff together is, for most things, the least convenient and simple. However, by using cordage to tie up and compress items in your backpack, it gives you a place to actually store cordage. Essentially, you are using and storing it at the same time. Ingenious, right?
