Cyanotypes are a low-cost type of photography that prints objects onto a cyan paper, which create a white outline print from lying in the sun.
The more simple kind of cyanotypes is also known as a photogram used more in the past.
They are made by putting objects either in a random placement or however you wish, and placing them on sensitised paper.
Mainly plants are used for this type of printing but also you can use objects which are solid based.
If it is windy out, you can use a sheet of glass which sets the items in place without misplacing them.