Heavy clothing and holiday eating are just a couple reasons why winter is the perfect time to "bulk up". In order to build muscle and size your body must consume a surplus amount of calories, resulting in eating large amounts of food. A dirty bulk, involves eating larger amounts of food with little attention to the micronutrients such as fiber or vitamins. While a clean bulk involves paying attention to the amount of food and the macro/micronutrients at the same time.
To put on size you first must calculate the amount of calories your body needs to maintain its current weight. Once you calculate your calories, increase that number by 500. In order to to gain muscle you must be eating more calories than you are burning. If you are lifting heavy and eating 80% clean most the time, you will be able to put on muscle while gaining minimum amounts of fat.
Since you are trying to eat more than you burn, you should limit the amount of cardio throughout the week. Cardio should be done 2-3x a week in the form of High Intensity Interval Training. Doing 20-30 min of HIIT will help lose fat while mainting muscle at the same time.
When it comes to lifting your reps should range from 6-12 for the most muscle growth. You should aim for heavier weights and sets lasting around 60 seconds. Your workouts should not be hours long, instead make it a sufficient 45-60 minutes.
Supplements can play a key role when it comes to seeing building serious mass.
If you have a hard time eating tons of food throughout the day, a mass gainer is the perfect way to get in those calories. Without having to cook for hours or spend money on meals, a shake can range from 600-3000 giving you those excess calories you need. In addition, a shake will give you proper amount of protein and carbs, giving you a clean, easy meal.
Bio Gro: allows for more protein synthesis = better recovery (more size and strength gains over time), better utilization of excess calories