Frequent tipster Leonid Nemirovsky sent us a couple of tips for working in 3D. "Never use 2D commands such as Rotate, Mirror, or Move in 3D. Instead use the 3D equivalents: 3Drotate, 3Dmirror, and 3Dmove. You can use the regular Rotate command while 3D modeling, but only when set to a particular view like Top, Bottom, Left, etc.
"Also, you can set a background image to render behind your 3D model. Use the View command to set a background image. To select the desired image, browse to it. You can use a JPG, or another image file type (GIF, TIFF, BMP, etc.).
Notes from Cadalyst Tip Patrol: In AutoCAD 2010, new tools were added that can simplify moving and rotating. They are the 3D Gizmos: Move, Rotate, and Scale. Also keep in mind that using the Dynamic UCS when modeling in 3D can be very useful too. Len's second tip can add a lot to your renderings. Start the View command, make a new one, or edit an existing view. Click on the Background option. You can choose from None, Solid, Gradient, or Image. The Edit option opens a new window where you can make adjustments to the background. Click OK. The image will be displayed when you are in a 3D visual style mode. It is fixed, but you can rotate your view or your model to best fit the image.