Turn clean jar upside down.
Practice using the water dropper to draw up water, then expel exactly one drop of water to the tip of the dropper.
Use water dropper to put exactly one drop of water in the center of the bottom of the jar, which is still turned upside down. Ensure that the water continues to adhere to the surface, as it is an integral part of your microscope lens.
Place your new microscope over objects around your house, ranging from water droplets, in which you may be able to view microbes if your glass is relatively small, to insects. Enjoy your new ability to view objects larger and in more detail!