Don’t Use Flash Indoors
Flash can look harsh and unnatural especially for indoor portraits. Therefore, there are various ways you can take an image indoors without resorting to flash.
First, push the ISO up – usually ISO 800 to 1600 will make a big difference for the shutter speed you can choose. Use the widest aperture possible – this way more light will reach the sensor, and you will have a nice blurred background. Using a tripod or an I.S. (Image Stabilization) lens is also a great way to avoid blur.
If you absolutely must use flash, then use a flash with a head you can rotate, and point the light to the ceiling on an angle.
To ensure you get the most flattering light for portraits, landscapes or anything else you want to capture