To create printable miniature dollhouse sheets, you can either download them from a specialized website, such as PrintMini.com, or create (or edit) the sheets using an image editing application, such as Photoshop or the GIMP. It is important to print the miniatures on the same scale as the dollhouse.
Typical miniature prints include two-dimensional objects, such as photographs, movie posters, rugs and wallpapers, and two-dimensional designs that can be folded into three-dimensional objects, such as boxes, books and pieces of furniture.
To create a two-dimensional object miniature print from an image, resize that image using an image editing program, such as Photoshop or the GIMP. The blog true2scale.com features a tutorial on resizing images to the right scale. The usual scale for dollhouses is 1:12; it is called "1 inch scale," because 1 scale inch corresponds to 1 full-sized foot. Other common scales are 1:6, 1:24 and 1:48.
To create printable three-dimensional object, you need to create or download a template of the paper model of the polyhedron that better resembles the object you want to create. The website korthalsaltes.com features two-dimensional models of common polyhedrons. Add texture or color to the paper model, and resize it to the appropriate scale.