To understand why we have it I'll explain...
1)God made us that way. Yes, it's absolutely incredible.
2)Some say it acts as a lubricant...I say, for what?
3) It's pH (scale of acidity or how basic), is slightly acidic. This is to keep the bugs (bacteria and fungus) at bay. Hence if too much of it is removed, you have a whole slew of problems popping up in those lil' canals.
So, the next question is how to deal with it.
Here is the list from least invasive to most invasive, and as long as there isn't a hole in the ear drum
1)Drop oil into the EAC (external auditory canal), these include Extra Virgin Olive oil, sweet oil, baby oil, mineral oil.
2)Wash it out in the shower
3)Don't use Q-tips, this over time shoves wax deep into the EAC causing an eventual impaction against the drum
4) Have your friendly neighborhood ENT doc pick, pull, scrape, wash it out on a yearly or so basis depending on the symptom accretion.
There are those with tiny ear canals...
Same as in previous steps 1-4.
5)Canalplasty-where the canal is opened wider surgically.
Those who produce lots and lots of it...
More often with steps 1-4
Dry ears...
Steroid cream works well here. Ask your doctor how often and for how long to use it. Also, there may be a fungal component to this. Lamasil drops usually work really well here as long as there isn't a hole in the drum.
Wet ears...
Skip the step #2
You can use 1/2 Acetic acid (vinegar) and 1/2 Everclear grain alcohol and put the drops in each ear after showers/bathing. This keeps the pH in the EAC balanced.
Last of all, DON'T USE EAR CANDLES! That is, unless you are into voodoo and that kind of jazz. Just look at Wikipedia for the explanation... or go to my super old post on the matter.
Why it gets dark?
When wax it produced down in the canal, it us almost clear. As it works it's way out the wax loses it's moisture and darkens to almost a black or very dark orange color. It is usually hard and crusty at this point.