Photoshop itself can’t handle 3D artwork, but if you have access to a 3D modeling program like 3DS Max or Maya you could make the model there and save a bunch of renderings. You’d rotate the image a fraction of a degree, save the rendering to a file, and repeat until the object had rotated 360 degrees. After saving all the renderings, you’d have to combine them all into one animated gif. As far as I’m aware, Photoshop doesn’t do animated gifs, so you’d need a program like The Gimp. You’d import all your renderings into Gimp and put them in order, then export the animated gif. Voila!