M102 is very easy to locate with a 10-inch reflector. The galaxy appears as bright, elongated NW-SE, with a brighter more concentrated middle. Two faint stars can be seen flanking the NW end of the galaxy. When increasing the magnification to 200x and then 290x, a third, fainter star could be seen relatively easy, SSW of the SE end of the galaxy.
It wil require at least a 4 inch telescope at a relatively dark sky to be seen brightly. It will begin to show both structure and its dark dustlane at apertures approaching 6-8 inches. For smaller scopes, it will appear as a thin streak of nebulosity.