Updated: Oct 4, 2021
The best way of getting in shape is to choose physical activities that you enjoy doing and do often. It should be fun and challenging, however, you need to think will you still be doing this in 5 years and if the answer is yes, you're on to a winner. When it comes to being physically active if you're not doing it, you're not getting any benefits from it. Enjoyment and fulfilment are key, if you do not have a good time you're less likely to keep it up. So keep it fun, but try to keep it challenging too.
The following information is general and not specific to you. Depending on your age, ability, fitness level and health, the information may not be appropriate to you, or it may need to be adapted. If you're not sure, seek professional guidance.
Now that's out of the way we can start talking about the more exciting stuff.
Step number one is to incorporate some resistance training, activities like lifting weights, working with resistance bands, heavy gardening and bodyweight strength movements (think push-ups, squats and pull-ups) count here. The aim is to develop a bit of muscle. We're not talking about looking like Arnold, think tone. Muscle has a calorific requirement to exist, that means that if you up the amount of muscle that you have you'll also be upping the number of calories you burn by just living. Start with at least two sessions of resistance training a week.
Step number two, add some intensity. In addition to your new resistance routine, you want to add a bit of high intensity to your week. You can do this by adding HIIT to your practice. HIIT is high-intensity interval training, you work at a high intensity for a short period and then take a brief rest. Working at the higher end of your capacity is an optimal area to burn energy, but you can only keep it up for a short time, so work as hard as you can within your capability then have a short rest. They're many ways to work at a high intensity, but HIIT is one of the more common you will see. Add it in a couple of times a week.
Step three, move a bit more. It's essential to up the amount of general activity you're doing outside the fitness realm. You will spend most of your life not working out so most calories you burn will not occur during a workout but during the day doing your usual thing. A simple way to up this is to sit less and move more. If you're driving to work, park further away so you can get a bit of a walk in. If you work at a desk, add in a bit of time away from it, get up and move around, grab a glass of water, stretch your legs for a bit, little things can add up throughout the day. If watching TV in the evening, get up and do some housework during the add break.
Something to remember is that this is all futile if you're not eating well. If you're overeating, it doesn't matter how much exercise you're doing. It's common to think you can out-exercise bad nutritional choices, but that is seldom the case. The issue is that people grossly overestimate the amount of energy used while exercising and they underestimate the amount of energy they are consuming. It's also not a healthy way of thinking, so nutrition should always be number one on your list.