The best way to view your slides is to use a slide projector. If you don’t have your own, these can be very difficult to find. Here are some alternate methods.
To view negatives and slides, many people just hold them up to an overhead light source, but this can be tiresome if you’re dealing with a large number. Ideally, you could use a lightbox; this is basically a light inside a flat, translucent plexiglass box – you might want to inquire at a school or library to see if one is available that you could use. They are also available to purchase from photographic equipment shops; you may feel it’s worth the investment if you have a great many slides or negatives. Box-type slide viewers are also available. If you just want an inexpensive setup to view a batch or two, you can set up a simple piece of plexiglass (translucent if you can find it, but clear will work nearly as well) positioned over a light source. Spread a white sheet, posterboard or paper on the floor, and place a desk lamp or strong flashlight on it, facing up. Lay your plexiglass across a couple of chairs or boxes above the light, and use the plexiglass as a viewing surface. A glass coffee table with a lamp underneath will also work. You may want a magnifying glass, loupe or high-magnification reading glasses as well if you’re working with many similar negatives.