I emphasize suggestions because they are just that, not any hard, fast rules to adhere to. 
 
And how you fit all of your gear into your pack is up to you; just know that packing cubes and compression sacks are your friend.  And less is more – I am proud to say that my pack has always weighed in well under the limit.  And bring some Glad/Ziploc bags, too (the gallon and quart sizes) – the ones they sell overseas aren’t quite as strong.
 
And as long as everything fits – preferably inside and not so much outside – in your pack, again, it doesn’t matter how you get yer stuff in there.  Your pack is gonna explode anyway as soon as you put your stuff down in a place; it’s like gravity – inevitable.  Oh, yeah, a big duffel bag that fits over your pack would be preferable to those “Airporters” as the latter aren’t quite as durable (though mine still survived).
 
Here are links to posts I’ve written about what to pack.
 
And what I referred to when I was in yer shoes:
 
Also, the World Race is evolving so some of what I or Christie have suggested might be moot…
 
Lastly, in Allison’s words, just get yourself on the plane.  I’d worry less about what you’re packing materially and focus on unpacking and processing the life you’re about to leave behind.  If you have to choose between packing or sharing conversation & coffee with a friend – pick your friend.  People > Tasks.
 
Not that I’m advocating procrastination, but God’s all about the eleventh hour (note that I don’t say “last minute”).
 
It’s all coming together y’all.  I’m so glad to have met you (and I’m not gonna lie, my eyes are watering a little as I type this) and am so stoked for you!
 
Peace and joy as we celebrate the why and for whom the World Race is all about. . .