- With the pen (permanent ink)/pencil, mark the name of the bacterial culture in the far left corner on each slides.
- For the broth culture, shake the culture tube and, with an inoculating loop, aseptically (see figure bellow) transfer 1 to 2 loopfuls of bacteria to the center of the slide. Spread this out to about a 1/2-inch area. When preparing a smear from a slant or plate, place a loopful of water in the center of the slide. With the inoculating needle, aseptically pick up a very small amount of culture and mix into the drop of water. Spread this out as above.
- Allow the slide to air dry, or place it on a slide warmer (see figure bellow).
- Pass the slide through a Bunsen burner flame three times to heat-fix and kill the bacteria.
- Place the fixed smears on a staining loop or rack over a sink or other suitable receptacle
- Stain one slide with alkaline methylene blue for 1 to 1,5 minutes, or carbolfuchsin for 5 to 10 seconds, or with crystal violet for 20 to 30 seconds.
- Wash stain off slide with water for a few seconds (see figure bellow).
- Blot slide dry with bibulous paper.Be careful not to rub the smear when drying the slide because this will remove the stained bacteria.
- Examine under the oil immersion lens.