You'll need clear embossing powder, dark colored cardstock, a bold stamp, and acrylic paint. I don't recommend using glazes, paint tinted with dye based reinkers, or paints other than acrylic. They won't produce the same results.
1. Emboss dark cardstock with your desired image. I used the CTMH flower stamp from the upcoming August Stamp of the Month, "Something Splendid" on Cocoa CS. Remember that whatever is embossed will stay the color of your cardstock. The embossing will resist the paint.
2. Cover your image with paint. I only paint in one direction and I like to use a wide, flat bristle brush so that the brush marks are visible. I only use a small amount of paint and reapply paint to the brush often. It produces a smoother finished look - as opposed to using a large glob of paint.
3. Allow paint to dry completely. Use this time to clean your brushes and paint materials. :)
4. Use a thick dry paper towel or baby wipe that is not overly wet (wring out excess water first). Textured cloths work better for this step than smooth cloths. Rub the paint away from the embossed areas. You may need to use firm pressure or even rub with your fingernail under through the cloth. Experiment with what works best for you. The paint will stay on the cardstock, but will rub away from the embossed areas.
Here is a card I made using my paint embossed flower. I used a colored marker to color the flower center yellow.