Sneak up on cuts
Mitersaw blades can flex during tough cuts in hardwoods, but you can prevent this by making your cuts in two steps. First, make an initial cut about 1⁄16 " to the waste side of your cutline. Then, cut to the line. The finishing cut, about half as wide as normal, will be cleaner and spot-on square. After removing the cutoff, as shown in the photo, nudge your workpiece closer to the blade until the teeth line up with the mark, and make the final cut.
—from the WOOD shop