Recently I had the pleasure of styling merchandise on a photo shoot for a catalog. Maybe you haven't given much thought to it but just every object you see in a magazine has been set in its exact position to trigger an emotional response from the viewer so hopefully they'll want to run out and buy it. Whether you have an event to arrange or a bunch of knick knacks that don't have a home, styling objects is an art that can be learned. A triangle or pyramid is not only strong in its physical properties but visually as well. Building levels of varying height stimulates the brain in a way that allows for the eye to wander up and down, back and forth, adding interest to a grouping that works well in reality or in a photograph. Here's a short tutorial on how objects interact with one another. Notice how the print on the right and birdcage on the left balance the sides of the grouping even though they aren't the exact same height and are not similar objects. To bring the eye forward, the stack of books ground the area with a horizontal line to break the multiple verticals. The candle is yet another grounding shape that's lower than all others. I've also deliberately brought in various textures and patterns to stimulate the viewer with the lines of the cage against the scrolls of the mirror. The spotted fur is yet another contrast against the smoothness of the books. Keep these things in mind when curating your set up but be careful to not go overboard with colors and patterns. While the objects are different, the color family they belong to are somewhat subdued and neutral.
Even if you don't have objects of different heights, here's an example of how things work in threes. Even though it's not a definitive pyramid, there are still elements that draw the eye back and forth.
Many people think of a coffee table as something that only has flat books or objects but building a vertical space for it breaks up the static quality of horizontal lines. The Nambe platter in the foreground replicates the triangular shape in a subliminal and unexpected way. This last example is how to build a triangle in a photograph. Notice how the dog is not very high but still acts as a point in the hierarchy because I've lowered the camera to table height. The model train is a strong horizontal reference which juxtaposes the angle of the books behind it. Next time you decide to just toss things on the table, take a moment to play around with their placement and engage your guests with your thoughtful styling. Good luck!