Keep in mind that if your metabolism is fast and depending on your physiological factors, "eating more" alone will not help gain weight. Say you eat a lot in one sitting, but after few hours, your body will start entering the "break down processes" trying to keep your body have enough energy. (instead of storing to gain weight, you will be breaking down what you have or stored) You have to eat at the right times and frequently so your body will be kept in "building mode" inside, avoiding any minor or major starvation modes. And of course, do not rely too much on unhealthy foods or weight gain supplements to help you gain weight fast either. Either they're bad for your health or are just helping to enhance appetite, which can have beneficial or advrse effects depending on your diet choice.
If You want to instant increase weight then wear heavy Coat as well as Wear fire safety shoes & never forgot to wear non-branded helmet. You must increase your weight 10kg to 12kg... Sure... If it is less then take 1 or 2 bricks in your hand and step up on weight machine. Please tell me what you think about my idea?.. Please tell true..OK... its an instant weight increasing technique...