The best arrangement of paintings on canvas is the one designed in detail and not at all improvised, as well as respectful of your own tastes. The first piece of advice is to hang the different images at a suitable height, i.e. "at eye level". That is, you don't have to make extra efforts to appreciate the framing, colors and depth of the painting. Let's say that, approximately, it is good to hang the paintings at a height of one meter and 60-70 centimeters, which is the average height of the person (however, if you plan to observe the prints mainly while sitting, this indication may vary downwards).
For greater harmony with the context, it will be necessary to check the presence and distances of corners and edges in the environment (windows, bookcases and so on). It is clear that the best thing to do will be to choose to arrange the paintings following an order that is as schematic and geometric as possible. For example, if you want to highlight the composition of images, placing it on only one side of the room, it will be necessary to intervene with a 'corrective' that harmonizes the visual effect on the other side of the context. Generally, when you arrange paintings based on a geometric order, you opt for shapes such as rectangle and square.
It is also a good idea to pay attention to the size of the furniture: paintings should not be hung above furnishing accessories and tables that are too small. As for the colours, you can choose substantial continuity with the rest of the room or insert certain prints as a breaking element, in a modern way. If there are certain colors that are repeated in the room, opting for "companion" paintings could be a winning choice in a harmonious way. If there is wallpaper or particular upholstery, it will always be a good idea to frame the print on canvas to make it stand out best.