First, you should locate the ISO adjust button on your camera. Some advanced cameras contain ISO button directly on their body. If you do not have it on your camera, then you will have to locate it in camera settings. If you find it difficult to locate the ISO settings button or onscreen option, then you can follow the instructions in the owner’s manual that came with your camera.
Once you are done with locating the ISO button on your camera, press it in order to enter its menu. Inside the main menu, you will find a shooting menu with a camera icon. Select it, and you will see the shooting menu, which you can use to adjust scene, white balance, ISO and many other shooting options. Here, you need to select ISO, which will take you to the ISO menu.
You can now select the ISO value from different options, such as 100, 200, 400, 800 and so on, depending on the quality of the camera you are using. The better the camera you have, the more ISO value options will be available to you. You can select the number you desire and try by taking pictures. The lowest value is usually fine to take high quality and sharper images.
If you get your desired results by setting the value to the lowest level, then you should not increase the ISO settings. If you feel that you are not able to take sharper images using the lowest settings, then you can increase the level by just one step and test the results. You can repeat the process until you get your desired results.