Espresso is the most important part of any coffee drink that involves it. Bitter espresso can ruin a drink entirely, and espresso with no crema can be watery and awful. Now, I’m no expert. I’ve been a barista for less than a week. However, I’ve been making espresso for as long as I can remember and I’ve been drinking coffee, (good, bad, and awful), for over 10 years. So trust me when I say that I know my coffee, I know good coffee, and I know how to make it. Here’s how to make perfect espresso:

1. Start with the machine.

The machine is so, so important. You’re just not going to make good espresso with a Keurig espresso pod. You don’t necessarily need a Rocket R58 (though if you can afford it, it’s pretty awesome). Do some research, read reviews, see what the professionals say (personally, I trust SeattleCoffeeGear). My personal advice is to pass up on machines that are mostly electronic, as they will likely break very easily and become irreparable as new machines come out and their parts cycle out. Pick a machine with a boiler. Pick a machine that’s mostly mechanical, because mechanical parts are easier to replace than electronic ones. Usually they’re (significantly) more expensive, but they’ll last much longer and they’ll be worth the investment. But if that’s out of your price range, keep in mind that a machine that doesn’t come with a portafilter you can remove, a group head, and a steam wand is not a real espresso machine.

2. Choose your beans wisely, and try not to buy a bunch at once.

Buy from a local roaster. Because you’re supporting a local business, you’ll be able to ask where their beans came from, and you'll know when they were roasted. This is good if you care about local businesses and fair trade, but it’s also good because you’ll know the date that they were roasted. It’s best to toss beans three weeks after their roast date so that they’re fresh. Stale coffee is bad coffee.

3. Store your beans carefully.

Pick a cool, dark, dry place where they won’t be exposed to the air, but do not refrigerate them because it messes with their pH. I don’t know the exact science behind it, but remember that stale beans are bad beans and will yield stale or bitter coffee that will not crema. If you store your beans well, they’ll last you that full three weeks.

4. Use fresh water.

Don’t leave the water sitting in the machine overnight. You wouldn’t want to drink water that you left on the counter all night. Plus, that just gives an opportunity for all kinds of bacteria to congregate and ruin your coffee and your day. Stale water means stale espresso, which equals gross. If there’s water in your machine from the night before, let it run into some sort of container until the machine is empty, then refill it with fresh water. And clean it frequently.

5. Pay attention to the grind.

It’s best to grind coffee out fresh for each cup rather than buying it pre-ground. It’s for freshness reasons, again, and if you’re not getting the vibe by now, the fresher, the better.

That aside, getting the perfect fineness for the grind is partly skill, partly guesswork. A good grind will let the shots pull slowly, about 27 to 30 seconds, but no longer or shorter than that. Experiment with your grinder until you get it, and you’ll be surprised what a good grind will do for the crema.

6. Tamp your espresso with exactly 15 pounds of pressure.

First, you need to distribute the coffee evenly -- it needs to be flat all the way around, and there are various ways to do this, including brushing the cone off the top or tapping the portafilter with your hand a few times. The espresso machine you bought should have come with an espresso tamper, but regardless of whether or not you have one, it is important that you tamp (or press down on your espresso with a flat surface) every time. The amount of pressure you use affects how fast the shot pours, which affects the quality of the espresso. If the shot pours too fast, you didn’t press down hard enough, and it will be bitter. If the shot pours too slow, you pressed down too hard, and it will be bitter. That 27-to-30-second mark is so, so important. What I’m telling you is, it’s a balance, and one variable being out of whack will make it all come tumbling down. You'll notice that the person is holding the tamper very precisely, like a flashlight. I have tendinitis and that puts strain on my wrist, personally, but I still make good coffee -- just hold your tamper in a way that works best for you.

7. “Use” your shot within 10 to 15 seconds of pulling it.

As if the 27-to-30-second mark wasn’t stressful enough, it’s equally important to serve or use your shot within 10 to 15 seconds of pulling it. This is because if it sits for too long, it will become (can you guess it?) bitter. Serve it immediately if it’s an espresso or doppio. And if it’s a latte, pour the milk into it immediately. If it’s a mocha, pour it into the chocolate sauce while you steam the milk. Essentially, once you add something to it, be it syrup, milk, or hot water, you’re golden (and your espresso is, too).

8. Learn how to tell a good espresso shot.

OK, so you followed all my steps, but how do you know if it’s a good shot or not? Well, good coffee is never bitter. There should be a nice, thick crema on top that, when you pass a spoon through it, reforms over the break. And it should be a nice golden color. Good espresso (and good milk) will help you make cool cappuccino or latte art.

When you have good espresso, you make a good drink. It’s really that simple. You can’t cover up bitter or sour coffee with vanilla syrup or perfectly steamed milk; people can always tell. This is just what I’ve learned after years of drinking coffee and making it at home, and a couple days of making it professionally. As I said before, I'm no expert. Maybe I’ll learn some of the science behind these methods soon, but for now, just trust me. And happy coffee-ing!