In the beginning, there was only you and the thought — the impulse to exercise.

That thought often does not come in the form of a great spiritual moment of clarity. More often than not, it comes from the realization that your jeans don’t fit, your body is now bulging out of places you had no idea existed or your inability to make it up three flights of stairs without gasping for oxygen.

So, here you are at a gym — nay, the human torture chamber — and all you can think is, “What happens now?” You could either turn around and run back to the couch, your favorite bag of potato chips and a pint of Ben and Jerry’s finest, or you could man up — or woman up, as the case may be — and tame the dragon.

You know what you have to do.

You know it won’t be easy. But if you choose to take the plunge, forcing your body to endure the suffering needed to reach your goal, you will be rewarded in pounds lost, inches cinched and measures of confidence.

That’s why you’re ultimately in the gym, isn’t it? You want to prove to yourself you can do this. You want to prove to the mirror you aren’t the person it reflects you to be.

So first things first: Be sure you are dressed appropriately. That means gym shorts, a t-shirt and tennis shoes are the style of the day. (You may wear a sweatband if you must, but please leave the kneehigh socks at home. The ‘80s ended more than 20 years ago.)

You don’t want your workout clothes to fit too tightly or be flamboyant — the gym is not a night club. You are there to work, and your dress should reflect that.

Find a vacant stationary bike or treadmill and pedal or walk at a leisurely pace for three to five minutes. The goal right now is to warm your body up for the work it will have to perform in the coming hour.

Use this time to reflect on why you are in the gym and what you want to get out of a daily exercise regimen.

Found your center? Fantastic.

For the workout, you will want to hit the weights first, then do a form of cardiovascular exercise. Your body needs to be able to work at its least fatigued when lifting weights. This will help you prevent injury and allow you to perform more repetitions with more weight.

Generally speaking, weight training allows the body to burn 200-300 calories per hour depending on the weight of the person and the intensity level at which they exercise. Weight lifting also is important because it helps promote fat loss.

For beginners, running through a full-body weightlifting exercise regimen is a daunting task, so for now, pick four exercises — preferably two lower-body and two upper-body — and complete three sets of 10 repetitions for each. The last repetition of each set of exercises should be hard and provoke the urge to make a nasty face. If you’re able to smile and giggle by your 10th rep, you’re doing it wrong.

This part of the workout should take between 20 and 30 minutes depending on your fitness level.

After you’ve worked up a sweat with the weights, it’s time to hit the cardio floor. As a general rule, the longer you are able to perform light to moderate cardiovascular activity, the more fat you will burn. And after all, burning fat is what it’s all about. If it’s been a while since you strapped on your running shoes, you might opt to tighten up your shoelaces and go for a stroll.

Though it is the easiest form of cardio, it won’t get you very far in the fat-burning game.

Now that you’re body is pissed off at you, it’s time to cool down. If there is a stationary bike around, you might pedal on it for three to five minutes like you did during your warm-up or walk leisurely on the treadmill. You must do something that requires you to move your extremities, but slowly. It is crucial that you stay slightly active at the end of a workout to promote blood flow throughout your body and to help kick-start the recovery process.

Get a drink of water, make a healthy food choice immediately following your workout and get a good night’s rest because tomorrow you’re going to wake up and do it all over again, right?