It’s an awkward situation. You and your girlfriend or wife have set the date and place for your summer vacation. It should be exciting. What can be better than tanning in the sun with plenty of suntan lotion, taking long walks along the surf, and riding the bike trails?

Unfortunately, you didn’t take care of yourself during the long winter months. While she continued to go to the gym, you spent a little too much time in front of your computer at work. By the time you got home, you were too tired to do anything but unwind in front of the TV.

You can just see yourself now — skinny arms and legs and a big belly. You will feel self-conscious all day long in your swimsuit or casual wear. Meanwhile, your woman will look stunning in her bikini, tight outfits or bike shorts depending on the plan for the day. Talk about contrast!

If you have trouble bulking up, you’re probably an ectomorph. If you’re out of shape, your condition is often referred to as “skinny fat.” It means you have scrawny muscles but a wide midsection.

What do you do? Call it off? No, it’s not the sort of wimpy thing someone like you would do.

Instead, you know exactly what to do: buff up your beach body so you look and feel good when you’re out there in the sun and sand.

4 Keys to Bulking Up Fast

How do you do it?

You have to do four things to get that lean, mean fighting machine look. First, follow the right advice. Second, eat the right proportions. Third, eat the right number of calories. And fourth, train the right way.

Let’s take a look at each one in turn:

1. Follow the right advice

Most skinny men have a tough time bulking up because they’re following the wrong advice. It’s not that the bodybuilding magazines are offering bad advice; it’s just that it’s geared toward mesomorphs – those with naturally muscular body types. Since you’re an ectomorph (on the lean side), it won’t work for you.

2. Eat in the right proportions

Mesomorphs do well on a macronutrient diet split of 40 percent carbohydrates, 30 percent protein and 30 percent fat. But as an ectomorph, you assimilate carbohydrates well. This is because you tend to have a more active thyroid, so you need more carbohydrates to get an insulin spike when you’re training. So a better macronutrient diet split for you would be 55 percent carbohydrates, 25 percent protein and 20 percent fat.

3. Create a calorie surplus

Most people who work out are trying to lose weight. They count calories, hoping to burn off more calories than they consume. Your mission, should you accept it, is to do the opposite. You can still count calories, but you want to have a surplus of calories.

Start with a 250 surplus, and then, as you get used to eating more, bump it up to 500 calories. As an ectomorph, you’ll convert these calories into muscle. But if you pass this 500 calorie threshold, you risk gaining fat.

Multiply your body weight in pounds by 15 to give you the right surplus. So, if you weigh 150 lbs, which is the average weight for an ectomorph, then you usually eat 2,250 calories to keep your current weight. Now add 500 calories to this and you’ll get 2,750 calories. You want to get that many calories in a day.

At first, it may seem difficult to eat that much, so start with just adding 250 calories. Then, once you’ve got used to eating that much, bump it up again.

4. Train the right way

The right way to train for a mesomorph is to have a five-day split, focusing on a different body part each day. This will not work as well for you. You need shorter, more strength-optimized workouts. You also want to emphasize compound movements that have a whole body effect like squats, deadlifts, presses and rows.

A three-day routine will do the trick. You can opt for either a Monday, Wednesday and Friday routine or a Tuesday, Thursday and Saturday routine. Aim for an average of two to four sets and five to eight reps per set. Your aim is to stimulate strength. A high-set, high-rep workout, known as volume training, will only exhaust you rather than help you bulk up. You will burn too many calories to gain weight.

You can find many strength training routines online that will fit within these parameters.

Should you do cardio? Yes, to develop your cardio-vascular efficiency, but only within moderation. If you are too intense, youyou will burn more calories than you can consume. A half hour of walking outside or on a treadmill three times a week should be plenty.

Consistency is Key

The biggest mistake people make when trying to bulk up is impatience. First, they are impatient to get their body used to eating more and becoming more physically active. It can sometimes take as much as three weeks to get enough momentum. Second, they are impatient over results. It takes the body time to transform, but you should see a noticeable difference in about 12 weeks.