Mise en place. Everything in Place.

1. Preheat your oven to 300° F.
2. Line two baking pans with parchment or silicone baking mats with printable macaron templates placed underneath. Secure the parchment for piping later with magnets or a heavy glass.
3. Prepare your piping bag with a small, round pastry tip. Snip a small bit of the corner off of the bag and slide the metal tip in with the smallest opening first. Push a little bit of the bag inside the large end of the tip. This will keep your batter from leaking through when you pour in the batter. 

The Steps

1. Firm Meringue: Give the egg whites and granulated sugar a piece of your mind on high speed for around five minutes. The meringue answers to you, not the other way around. You can rain in the sugar with the mixer running after the whites are foamy, but it's not a deal-breaker. I often throw everybody in the pool and flip the switch on my stand mixer. Meringue is done when it looks like shaving cream. For a firm meringue, the peaks curve off the tip of the beater like a bird's beak. If your egg whites look lumpy, separated, and are leaking liquid, you took it too far. It's actually pretty hard to do this when whipping egg whites with sugar. But sadly, you will need to begin again.
2. Macaronage: Sift the almond flour, salt, and powdered sugar directly into the bowl with the firm meringue. Discard any large pieces remaining in the sifter or sieve. I like to mix the ingredients a bit rough at first to bring them together. Then fold gently, scraping around the sides of the bowl and up over the top of the batter. You want a macaron batter that is smooth, shiny, and ribbons off the spatula. Any batter drizzled off the spatula should settle back into the collective mass in ten or twenty seconds (a long moment). Testing a small drop of batter on a plate is a great way to see where you're at. Better to be slightly under-mixed than over-mixed.
3. Pipe & Tap: Immediately transfer your batter to the pastry bag. Twist the top of the bag and hold it tight with your dominant hand. Steady the bottom with your non-dominant hand. To pipe macaron batter, hold the bag vertical and about a quarter of an inch above the pan. Squeeze until you just about reach your desired size or the inside edge of the guides. Immediately stop squeezing and flick away the pastry tip in a circular motion. If the tops of your piped rounds don't settle flat, gently tap the bottom of the pan. But by all means, don't take out the day's stress on your pan of piped batter and bang it on the counter.
4. Rest: In full disclosure when I first published this guide circa 2011, I described in detail how resting macarons is overrated. I still think it is to a degree. But I've learned from experience it's also great insurance. Drying out the tops of the shells a little can help them rise evenly when they hit the oven. And maintain a smoother dome shape. However, I often toss a full pan of macarons straight into the oven and succeed. You'll always get a few that don't turn out, those are for quality control.
5. Bake: Bake the macarons until the tops are dull and the batter is set. An easy way to check is to gently nudge the top of a couple of macarons with your finger. If the tops don't shift away from the bottoms, they are done. You can also lift a corner of the parchment or baking mat and check the bottoms. If the shell sticks, bake a few minutes longer. Remove the baked macarons from the oven, and cool for a few minutes on the pan. As soon as you can handle the shells, gently peel them off by pressing up from underneath the parchment or baking mat.

Fill & Serve

1. Match your baked shells into like-sized pairs. Any odd macarons are for the baker. 
2. To pipe your filling, transfer it to a piping pag or plastic baggie and snip a tiny hole at the corner. Leave space between the edge of the shell and the filling. This is the classical, professional standard. Macaron fillings should not be right up to the edge of the shells. And the mound of filling should not be as high as the shells. Otherwise, the fillings will ooze out when you take a bite. 
3. Store finished macarons in the refrigerator. But always serve at room temperature. Unfilled shells can be packed carefully and frozen.