The stages of the trichomes affects your ratio of THC to CBD. If you want a more energetic fun high then shoot for more THC; a more medicinal bud will contain more CBD. The CBD of course does not make you high but it does alter the high.
The first stage of those trichomes after they lift off like a golf ball on a tee is clear. They have little to no THC at this stage. The next stage is cloudy white. When they turn white they are filled with THC and small amounts of CBD depending on the strain. You will notice many clear ones still remain, you will usually have some trichomes in all stages of growth. Finally when they turn amber your THC is converting to CBD.
You want to shoot for maybe 10-30% amber depending on the strain and what you want out of it. Don't worry about the hair color, it can give an idea of the stage but looking at the trichomes themselves is the most accurate way.