Again, a very frequently asked question. Warming up, as the name suggests, means some gentle stretching movements that you do before starting to workout. This helps your body to warm up and improve blood flow. Stiff muscles get relaxed and you also get mentally prepared to start your exercises. Warm up exercises can be different for different people. You can try out different exercises and ultimately decide which ones will work for you. You can try gentle stretching movements, static jumping, skipping etc., depending on what makes you feel most comfortable. Judge for yourself what works best for you.