By using ubiquitous office badge clips with attached strips, I created an easy to apply hanging mechanism that goes on, and comes off, easy as pie.
This works great if you have gutters. You may find a way to get it to work without them, but I guess it would depend on your roof.
Step 1: Get some office badge clips
I hung 5 strings of lights, with 25 lights each, with 30 badge clips. That's 6 clips per string of lights. These are the strings with the large bulbs. Strings with the small bulbs could probably use fewer clips. I also used a few extra badge clips here and there as I went around corners or encountered other obstacles, so get a few extra.
Step 2: Check your lights
See if you can get your dog to help you out.
Step 3: Attach the badge clips
You want to have the clip part underneath the strap, and rotated around so that it faces the string of lights. That way, when you attach it to the gutter, the strap goes out over the edge of the gutter and the string of light hangs down in front of the gutter.
Step 4: Hang your lights
Then just repeat these steps with the rest of your strings of lights until you're done.
When it's time to remove the lights, I'm just going to leave the badge clips on for next year.
Of course, if you get up there and discover that your gutters are stuffed full of leaves, it might take you a little longer.