I was able to fit everything into an Osprey Farpoint 55 liter backpack, which includes a zip-out daypack, so I was probably able to get a little more room.  It holds more than I thought it would.  Here's my packing list:
​Clothes:
1 lightly-insulated running jacket
​1 non-insulated rain jacket with hood
​4 long-sleeve REI shirts with roll-up sleeves
​1 black tee shirt
​2 pairs of convertible pants/shorts
​1 pair running shorts
​1 running shirt
1 pair running shoes
​1 pair swimming trunks
1 swim/board shirt
5 pairs of boxers
5 pairs of socks
​And when traveling will wear a pair of jeans, my Merrell hiking shoes, and another REI shirt
​Other:
​2 small towels in case the hostels don't provide
​1 cocoon sleep sack
Money pouch, hidden underneath my shirt to hold my passport, credit cards, ATM card, license and some cash.
US$400 emergency cash that will be hidden in various places in my luggage
​Standard toiletries
​Swiss Army knife
​15 feet of parachute cord to dry clothes
​Re-usable shopping bag
​Cool rag and handkerchief
Padlock for hostels
Probably too many electronic devices: Laptop, wireless mouse, iPad, iPhone and Fitbit Surge (and all of the cords)
Headphone earbuds
​Universal adaptor
Notebook/journal and pen/pencil
​Collapsible 70 ounce water bottle
​One deck of cards with 5 feet of duct tape wrapped around it
​Four packs of Kleenex
​Ziploc bags, safety pins, twist ties, and needle/thread that Mom gave me
​Sunglasses

​It will be interesting to see how this packing list changes as I travel...

Three days until I leave on my trip.  Getting things in order...
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