It’s remarkable that a simple seed can contain such depth and breadth of flavor. Like the coffee bean, Jessica Easto’s book “Craft Coffee: A Manual” (Agate Publishing, $19.95) dives deep and reaches wide as it teaches consumers how to improve their daily cup.

Coffee, the drink, is made up of but two ingredients: water and beans. But there’s much to learn about choosing equipment, buying beans and heating water. Even the way you pour water over grounds affects your cup of joe.

Today, thanks to farmers, importers, roasters and baristas, coffee quality is high. It’s realizing that quality in your home-brewed cup that can seem out of reach. But with a bit more time and money, better is possible, Easto says.

Easto came to coffee enlightenment via “a circuitous road paved with ignorance.” In high school she ordered her first cup of coffee black because she didn’t realize people expect plain coffee to be bad and dump in sugar and cream to make it palatable. In graduate school she bought a pour-over device, only because a machine seemed extravagant for her single morning cup.

Enter her friend Andreas, a barista who noticed her manual coffee maker. He showed her a couple of ways to improve her brew. She learned that coffee, when brewed manually, can be manipulated for best results. Revelation! She married Andreas and was on her way to coffee nirvana.

Easto writes as a home coffee brewer living with a professional. (Andreas is now a technical specialist for an espresso machine company.) Her book offers comprehensive knowledge, some of which the casual home brewer may want to skip, such as “Rwandan flavor notes include raisin and other dried fruits.” Instead, latch onto her practical advice.

The equipment

Start with equipment, since your brewing method affects everything else. The first question is manual devices versus automatic coffee makers. Easto focuses on manual because decent automatic machines are so pricey. “Manual methods allow anyone to make cafe quality coffee at home,” she writes.

(If you do want automatic, check out the Specialty Coffee Association’s list of certified machines.)

Manual devices fall into two categories: immersion and pour-over. Prices don’t include disposable filters. The former includes:

French press: Good for beginners. Versatile, since you can also make cold brew or cafe au lait in it. $17 to $70, depending on design and material.

Aeropress Coffee and Espresso Maker: “There isn’t a faster brewing time with such tasty results,” Easto says. Works well with various grind sizes, brewing times and water temperatures. Finer grinds produce less acidic coffee. About $30.

Abid Clever Coffee Dripper: User-friendly. Uses a paper filter, which produces a cleaner taste. About $22.

Pour-over manual devices require a steady hand with the hot water. (The amount of time that water is in contact with grounds affects how flavor molecules dissolve.) A slow, controlled pour produces better results. Pour-over devices include:

Melitta: Good for beginners. Affordable. “The first that allowed me to taste different flavors in coffee,” Easto says. $4 to $30.

Bee House Coffee Dripper: Affordable. Compatible with grocery-store filters. Fits most coffee cups, allowing you to pour-over right into your cup. $19 to $33.

Walkure: This Dutch device, which Easto says is “easy on the eyes and easy to use,” is pricier than most pour-overs or drippers. Doesn’t require a paper filter but produces a cleaner brew than other paperless devices. $89.

The method

Choose one device, and learn to use it, so you can focus on other variables such as grind, water and beans. Grinding whole beans just before you brew is best, but ditch the blade-style grinders. That spinning blade results in uneven grind sizes, which means uneven flavor extraction. A burr grinder, electric or manual, is more even and lets you control the size.

If you don’t want to buy a burr grinder, ask your coffee shop to grind a week’s worth of beans for you. This results in a trade-off in freshness, but beans ground to the optimum size for your device beats fresher beans mangled by a blade grinder, Easto says.

Your tap water is likely fine; a simple carbon-filter water pitcher may improve it. Don’t use distilled water or mineral water, which makes coffee acidic or dull. And reverse-osmosis water filter system? Unnecessary, in Easto’s opinion.

Use water that’s just off the boil, not boiling. Boiling water dissolves too many compounds too fast, resulting in bitter coffee.

The most important variable is beans.

“No matter how carefully you make coffee, you can’t create quality,” Easto says. “It must be there to begin with.”

Do

Skip the grocery store. Most have a limited selection of quality beans. Find a roaster in town or online.

Ask questions. Where did the coffee come from? What’s it taste like? Staff should be able to steer you to a coffee you’ll like.

Buy fresh, buy often. Look for a roast date on the bag. Coffee goes stale quickly. Buy only what you’ll use in a week.

Don’t

Buy in cans. Craft coffee is sold in bags, usually with a valve in front that helps keep it fresh. That one-way valve allows air to go out without letting air in. In bags, you can squeeze air out to reduce oxidation. “You can’t squeeze air out of a can,” Easto says.

Buy flavored coffee. Craft coffee has inherent flavors. It doesn’t have flavor added to it.

Also, beware of words like bold, full-bodied, dark, or French or Italian roasts. Craft coffee producers are unlikely to use those terms.

Once you’ve scored a bag of quality beans, store it as you would a spice, in an airtight container in a cool, dark, dry space. Keeping it in the original bag is fine (squeeze that air out between uses).

Keep the bag away from water and steam. Don’t put it in the fridge, where it can absorb odors. Experts debate whether storing in the freezer helps, but it likely won’t negatively affect your beans.

Buy quality beans, and handle them right, Easto urges, and you’re well on your way to a better cup at home. “Coffee is a fickle beast. It’s swayed by external factors, from the weather to the water to your eager hand.”

Cheryl Stritzel McCarthy is a freelance writer.