Giacomo’s tips

Use a 50mm lens, any brand is fine. You do not need a tripod: choose a subject (anything will do, really) and get your camera close to the subject. You will need to get very close to get the focus. As the lens is reversed, be careful not to scratch it, especially when it is brought near the camera body. Set the ISO and shutter speed according to the natural light you have available, doing some tests.