When a room gets overwhelming to me, the first thing I do is take a few things out. Sometimes simply clearing the space can refresh me.
via designsponge
That can happen with more than just decor items. Sometimes colors and textures can be overwhelming too and just taking one piece out can help you find that balance.
My favorite rooms are ones that are so elegantly put together but somehow the most simple of all.
Try not to clutter rooms that don't need extra decor. Small rooms are the best example for this situation.
What rooms would you simplify right now if you could?