Fade is a style wherein gradually the length of your hair goes on decreasing as it goes from the top of your head to the Nape of your neck. This is a gradually trimmed style at best. The undercut is a style where in the the length of the hair does not decrease gradually but there is a sudden drop in its length. That is an even more bold look.
These two styles make the mohawk appear even more interesting because they shift to focus directly to the mohawk. Especially for men with scanty hair or men that keep the length of the hair short, you should surely opt for fade or undercut. This combination will make your hair appear thicker and well balanced.