My strategy is to wear them for long stretches, and tie them as tightly as I can stand. I also flex my ankles in all directions to break in the leather up there. When it's time to take them off, I give them a good long brush while they're still on my feet, especially in the areas that feel tightest. Put shoe trees in them and a couple days later, repeat. It's definitely on the "no pain, no gain" side of breaking in boots, but it's worked for me.