On this deck build, I show you how we cut deck joists to finished length the way pros do it—without measuring 50,000 times and without letting a slightly imperfect house turn your frame into “wobble wobble.” I set my band joist locations and mark the finished length, but I leave the field joists running a little proud and what I call “wild.” Then I run a string line from my reference screw to my corresponding mark so I know I’m dead straight for the full run. Once that line is pulled tight—Snapsville 9000—I use a layout square to transfer the line across each joist and make my cuts. I’m using a left-bladed worm drive (Wormy McQuiry), and I’ll tell you why: as a right-hander I can see the blade, and that little pommel helps me force the shoe tight to the work for clean, square cuts. After the joists are cut, I talk through the next step—reinstalling a 2x6 cleat along the run so the front band can sit proud and give you solid inside support, especially if you’re planning housed guard posts.