Protozoans are a group of animal protists of more than 50,000 species and are found under almost all natural conditions where there is moisture. A protozoa11 is not as simple an organism as one would think it to be. It is so designed that even though it is a single cell, it still functions as a complete organism.
The slides that you will get for observation will all be permanent, stained whole mounts. While observing them you should sketch them as accurately as you can. You will note that as you sketch the specimens under observation you are more likely to look for details you would not see otherwise, and if you put those details in the right places in the sketch and in the right dimensions, you will recognize the specimen when you see it again.
Sometimes you may not be able to see all the details in a single specimen but by observing several specimens and drawing a composite picture from your observations you will be able to recognize the specimen in any given slide. Color coding also helps. You can devise a color coding system for yourself, for example blue for the nucleus, green for the chloroplast, etc.