To calculate the magnification of the object you are looking at, simply
- multiply the eyepiece magnification with the magnification on the objective lens.
For example. If the eyepiece has a magnification of "X10" and the objective lens has a magnification of "X20" then the object you are looking at, is magnified 10 X 20 = 200 times.

*Hint- Never move the stage towards the objective lenses while looking through the eyepiece. This will surely result in damage to the slide and more importantly damage to the objective lens.
Setting up your microscope.
1) When moving the microscope from place to place always place one hand under the stage .
2) Place the microscope in front of the light source and adjust the mirror so that maximum light comes through the body tube and into the eyepiece.
3) Prepare your slide and place it on the stage. Use the clips to hold it in position.
4) Focus the slide as described above. Always start with the lowest magnification first.
5) Move slide around slowly on the stage so that you can locate other objects.