Here's a few tips to make that portage a little bit easier.
It's always awkward when you have to carry long items, like paddles and fishing rods, so I find it best if you can strap them into the boat, and I do that with pieces of Velcro. Cut it to the length you want, and it's just a simple matter of wrapping it around and fastening it in, and the stuff is there. It's not going to move on you.
Now when you're carrying the canoe solo, you carry it from this middle piece. This is called the yoke. The nicer ones have this curved section, which sits on your shoulders really nicely. But even this, on a long portage, can dig in and hurt. So they make this foam padded cushion that kind of straps on with Velcro, and it makes it a lot easier on your shoulders. If that isn't enough, then I recommend wearing a life jacket, as well, for a little extra padding.
Video courtesy of: www.explorethebackcountry.com