Carry your microscope in both hands. Grasp the arm of the microscope in one hand, and use your other hand to grab under the base of the microscope for support. When putting the microscope down, make sure you put it down on a level, flat and stable surface, free from obstructions. Don't place it on a book or a stack of books.
The microscope is a very sensitive, finely-calibrated instrument. If you handle it gently and carefully, it will last a long time.
Prepare your slides with a cover slip or cover glass over the specimen. Don't view your specimens without a cover. The reason for this is to protect the lenses.
Fasten the slide with the stage clips. This will secure it and minimize the chances of your image shifting as you try to focus in on your specimen. Push down on the back end of the stage clip to open it.
Switch on the microscope's light source. Adjust the diaphragm to the largest hole diameter, which allows the greatest amount of light to come through. With an iris diaphragm, slide the lever to allow the most light to come through.
Adjust the coarse focus knob (the larger knob) while looking at the stage and objective lens from the side (not through the eyepiece). Turn the coarse knob so as to move the stage closer toward the objective. Adjust it as far as you can without touching the slide.
Rotate the nosepiece (the part of the microscope with the lens closest to the specimen) to the lowest-power objective. This is usually 4x magnification. The eyepiece is 10x, giving you a magnification of 40x. You will get a wider field of view if you start out with the lowest-power lens. Once you have the specimen in position, you can switch lenses to a higher power.
Look through the eyepiece(s) and adjust the lighting intensity of the illumination until you attain the maximum but comfortable level of light. The adjustment you make will open or close the diaphragm, allowing more or less light to come through.
Turn the coarse adjustment knob to bring the image into broad focus. You should turn the adjustment so that the stage moves down and away from the slide. Adjust the stage until the image comes into broad focus. Use the fine adjustment knob to bring the image into near-perfect focus.
Move the microscope slide so that the image is in the center of your view through the eyepieces. Readjust the lighting as necessary.
Change the low-power objective lens to the next level higher-power objective lens by turning the nose-piece. Adjust the fine-adjustment knob to maintain a clear image.
Lower the stage when you are finished. Turn the nose-piece to bring the low-power lens into position. Remove the slide. Turn off the microscope when it is not in use.