Determining the Space -
Foremost, you have to determine the available space and then search for paintings. As per the rule of the thumb, an artwork should not cover more than 2/3rd or 3/4th area of the wall.
Consider scale & Position - The position of the painting should be at the center of the wall, leveled at your eyesight. Usually, it is 60 inches from the floor.
Color Scheme of the Painting - It becomes a bit complicated when it comes to choosing the color of the painting for a room. The simple rule is that the chosen painting should have colors similar to the interiors of the room. Completely odd colors can be eye-catching but in a negative sense as colors will clash with each other.
Matching the Theme - The painting you are going to hang on your wall should not clash with the theme of your room. If the artwork has any content like graphical patterns, animal, landscape, portrait, flowers etc, ensure that it blends with the theme.
There is a great range of options available in wall tiles in terms of designs and properties. Here they go.