1. Eat a healthy balanced diet
While this may seem the most obvious on the surface, this is the one thing most people choose to neglect over everything for some reason. What you put into your about is about 75% of your fitness program; QUIT NEGLECTING IT!!! If you are looking to gain some muscle mass then you will want to eat more calories than you consume and if you are looking to lose weight then burn more calories than you consume. You also want to make sure that you are eating low-glycemic foods (foods that will not spike your blood sugar). This is a bigger problem than people eating too much fatty foods because a good portion of the time, these foods are labeled "fat-free!"
2. Weight/Resistance Train
To achieve any fitness goal whether weight loss or muscle gain, you should be lifting weight at least 2 times per week but preferably three. People who are looking to gain muscle should eventually work their way up to 4-5 days of resistance training per week. Building muscle will help increase your metabolic rate which will help you burn more fat! Weight training also helps build strength, improve balance, increase core strength and help you look better!
3. Sleep
Our body needs sleep in order to recover from the events of that day. If you do not get at least 7 hours of sleep per night, you won't properly recover and impairs you physical and mental function the next day. Not getting enough sleep can also lead to an increase in appetite and unwanted weight gain.
4. Drink Water
A very easy way to determine how much water you should be drinking is dividing your body weight by 2 and that number gives you the ounces of water you should be drinking each day. For example, if you weigh 180 pounds, you should drink 90 ounces of water daily. Your body is at least 50-60% water so do not deprive your body of half of its makeup!
5. Improve flexibility
Improving flexibility can be done a couple of different ways, but the way that has been most effective for me is yoga. I do not do as much yoga as I probably should but I have always gotten my best results when I implemented yoga into my fitness program 2-3 times per week. Yoga is also great for improving core strength and stability. Stretching is another good way to keep your muscles flexible and strong. Static stretching should NEVER be done BEFORE you work out! This may actually increase your chance of injury! Opt for dynamic/active warm-ups BEFORE you work out and static stretching AFTER your workout.
6. Cardio
Most people understand the benefits of cardiovascular work and that it should be done 5-6 days per week ideally. The fitness goal I would like to focus on here is the muscle gainers. YOU STILL NEED TO DO CARDIO WHILE BULKING!!! Just because you are trying to gain weight and put on muscle does not mean that you should stop taking care of your heart! Now this does not mean you should be doing 5-6 days of cardio per week. Doing cardio does not translate into "losing gains", if you eat more calories than you burn then you will still gain weight. The bonus of doing 2-3 days of cardio per week while bulking is that you can fight off the fat gain to a degree and still put on muscle! The scale may not move as fast as you want it to but A) the scale does not tell much of the story of your progress and B) what good does it do to gain weight there is not any muscle mass accompanying it?
7. Supplementation
Supplementation is definitely the last piece of the puzzle. You absolutely need to have to previous 6 categories down pat before you look at taking any supplements. If you can't be consistent with all 6 categories above, then supplements will end up being a waste of money for you for two reasons. First, supplements are meant to SUPPLEMENT a fitness program, not replace any part that may be lacking. Second, if you have no consistency with anything else then you will not be consistent with your supplements and supplements need to be taken consistently to have their desired effect.