For the holy atmosphere, the first thing that you should consider is lighting. You can install the lighting here and there. However, you should make sure that you choose the dim color lighting so that you can keep the atmosphere to be holy and warm. After that, you can consider the ornament that you will bring to your home decoration.
It is better for you to bring the colors that can create a warm atmosphere like green, brown, beige, grey, or other neutral colors. That will be functional during winter so that you can get comfort inside your home. It is amazing how colors can work well and influence home decoration in a wide scale.