Here is my blow-by-blow account of our Quetico portaging regime. My canoe trips are always two-person adventures (my wife and I).

Almost always, we follow these steps...

1. Upon landing, we unload the canoe and set everything off to one side of the portage landing area (to get it out of the way of any others coming through).
2. I lift the canoe out of the water and set it off to one side.
3. We both change into our hiking/portaging boots (we don't do this if the portage is 100-200 metres or less and likely to be flat and easy).
4. I zip the life jackets around the bow and stern seats and attach the plastic bailer to the stern.
5. We put on our main packs (one each) and carry them (and a paddle, a divers' box holding camera & valuables and a couple of folding camp chairs) through to the other end. In case of a very long portage, we might shuttle things to the approximate halfway point and then continue from there).
6. Our second trip through has my wife carrying the food barrel (and a paddle) and me carrying a day pack and the canoe.
7. At the other end, we change back into our paddling shoes , I unzip the life jackets and bailer and then lift the canoe back into the water.
8. We load the canoe, take one last look to make sure we haven't forgotten anything and set off.

Like Mastertangler, I like to see what the route is like before carrying the canoe and also for my wife she feels more sure-footed and stable with her main pack than with the barrel so that's why we carry the main packs through first.

This may not be the most efficient method but we've become so used to it as a routine that it has become completely automatic.