You’ve decided you want to lose 20 pounds. Great! So, um, what should you be doing to get started and reach said goal as quickly as possible?

Weight loss — whether the number you have in mind is big or small — basically comes down to burning more calories than you take in. You can make that happen by eating less and moving more (and maybe giving your body an extra nudge with a few lifestyle changes).

But within those guidelines are lots of smaller strategies for maximizing your efforts. That’s where these pro tips come in.

Keep in mind that losing 20 pounds “quickly” doesn’t mean losing 20 pounds in a few days, a week, or even a month. Healthy, sustainable weight loss generally happens at a rate of 1 to 2 pounds per week.

These strategies can help you hit your goal as quickly as possible without falling into the realm of crash dieting (which won’t keep the weight off long-term and could be unsafe).

Remember: Weight loss basically comes down to burning more calories than you take in, so you’ll need to cut back on your food intake in order to lose 20 pounds.

Since a pound of fat equals 3,500 calories, that’s the amount you’d need to burn to lose a pound. You can eat 500 fewer calories per day to make that happen in a week or 1,000 fewer calories per day to lose 2 pounds in a week.

Cutting more calories than that falls into crash-dieting territory, which generally isn’t recommended.

Protein helps you feel fuller longer — which can make it easier to avoid eating extra calories. And that can help you reach your get-lean goals.

Research shows high protein diets are tied to decreased belly fat, increased muscle mass, and higher metabolism during weight loss.

And you don’t need to go full-on Atkins to reap the benefits. One study found that upping protein intake significantly curbed people’s appetite and cravings.

Like protein, fiber is your BFF if you’re trying to lose weight. It moves through your gastrointestinal tract slowly to help you feel fuller longer, which can stave off the urge to snack, snack, snack.

So how much do you need? Research suggests that getting 28 grams or more of fiber per day can help reduce weight, trim inches, and prevent weight gain.

A cup of cooked oatmeal (4 grams of fiber), a cup of raspberries (8 grams), a quarter cup of cubed avocado (2.5 grams), and a cup of chickpeas (12.5 grams) will just about get you there.

You probably already know it’s not a great idea to go overboard on the baked goods, white bread, white pasta, or white rice — especially if you’re trying to lose weight.

Refined carbohydrates spike your blood sugar, which can cause cravings and lead you to eat more than you need. And research has shown that people who eat more refined carbs tend to have more visceral fat than those who eat whole grains.

One of the many good reasons to stay hydrated: Water’s a proven hunger buster. Downing a glass of H2O can temporarily satisfy a rumbling tummy until it’s time for your next meal or snack, so you’re less tempted to reach for a handful of crackers or chips.

It can also take up space so you eat less at mealtime. In fact, one small study found that people who drank water before meals consumed fewer calories.

Wolfing down your food is an easy way to take in more calories than you need, since it takes your brain about 20 minutes to register that your stomach is full.

Research also shows that eating at a leisurely pace is tied to greater feelings of satisfaction after you step away from the table — so you’re less likely to be craving a cookie an hour after lunch. If you can, try stretching your meals out to 20 or 30 minutes.

There’s something about those hours between dinner and bedtime that makes it shockingly easy to snack. In fact, research shows that late-night eaters tend to take in around 500 more calories per day than those who eat earlier.

The fix? Pick a time each evening — like shortly after dinner — to close the kitchen. Wrestling with the question of “Should I polish off that pint of ice cream while I watch one more episode?” is a whole a lot easier when you already know the answer.

If it’s anything other than water (or unsweetened coffee or tea), you’re taking in liquid calories that aren’t helping you feel fuller but are adding to your waistline.

Case in point? You’ll get around 125 calories from a 5-ounce glass of red wine, 150 calories from a 12-ounce latte made with whole milk, or 170 calories from a 12-ounce bottle of sweetened iced tea.

That’s not to say calorie-containing drinks have to be off-limits for life. But when you’re trying to lose weight, it’s worth keeping them to a minimum. And when you decide to have one, factor it into your overall calorie intake for the day.

You know cardio is a must for burning calories. But did you know that high-intensity interval training (HIIT) — alternating short bursts of speed with slower recovery periods — can help you torch up to 30 percent more cals than other types of cardio in the same amount of time?

Best of all, you can totally incorporate HIIT into whatever workout you’re already doing. If you’re walking, for instance, try alternating 30 seconds of sprinting with 1 or 2 minutes of walking.

High-intensity cardio isn’t the only type of exercise that can help you torch mega cals. Strength training preserves and builds lean muscle mass, which helps your body burn more calories all day long.

In fact, a 2012 study found that just 10 weeks of resistance exercises helped participants boost their calorie burning by 7 percent and shed 4 pounds of body fat.

Full disclosure: Meditating or journaling alone probably isn’t going to help you reach your weight loss goal.

But unchecked tension or anxiety can make it harder to drop pounds, since excess levels of the stress hormone cortisol can trigger the urge to snack and signal your body to store more fat.

If you want to give your eating and exercise efforts some extra support, find something that helps you relax and unwind — and make it a regular part of your life.

Sleep and weight are closely related: The less sleep you get, the more likely to you are to have a higher body weight.

There are lots of factors at play, but one biggie is that sleep deprivation makes you hungry — research has found that it even makes people more likely to pick less-healthy foods over healthier ones.

Your get-lean game plan, then? Aim to get 7 to 9 hours of shut-eye every night. Doing so just might help you get to your goal weight a little faster. (And at the very least, you’ll feel more well-rested!)