Tools
The only safe tools to hand a neandrethal are a hammer and an anvil. With these he is able to best express his natural talents to bludgeon. Most tools, however, are too dangerous. A twist drill, for example, can be used to scratch or gouge a piece of wood; but one should never allow it to be inserted in a drill press. A torch could be used to club a wayward squirel into lunch. Allowing a neanderthal to light it is dangerous and may lead to flesh burns and structure fires. If a neandrethal has not completed his quest for fire, don't help him along
Words
Neanderthal should exercise care with most words. They should stick with monosylabic words that express basal emotions. Words such as ugh, uhh, duh, huh, and wow are a neanderthal's best friend. Two and three syllable words are most dangerous since they instill a false sense of security. They should be used with utmost care. Under no circumstances should they be used to form advanced constructs such as similies, analogies and metaphors. Polysylabic words are unwieldy to pronounce and too complicated for a neanderthal to understand. However, some 'high functioning' members of the species have used such words to bludgeon unsuspecting listeners into submision
Color
A neanderthal can only consistently distinguish black and white. Grey areas are too confusing and can only be navigated with expert guidance. A neanderthal sees only one color: red. Like a moths to a candle, neanderthals are attracted to this one color. They can be held grinning in stupor by a simple red blanket until they finally die of dehydration. This is a well documented condition that scientists speculate is an outgrowth of the pleasure they experience when bludgeoning something into submission. Crimson is a color that engenders a particularl bliss in most neanderthal. The common street signal cannot be negotiated by the species - they stand transfixed at red lights for hours.
Humor
Amazingly neanderthals do experience a primitive sense of humor. They can understand slapstick, some wisecraks and nonesensisms as long as they are composed mainly of monosylabic words and play on basal emotions. In generals neanderthals should not try to be funny. Repartees often turn into insults and witticims are often bitting.
Electronics
Neanderthals should not handle any kind of portable hand-held electronic equipment unless its meets U.S. Army Development Test Command MIL-STD-810F spec, is encased in rubber and attached to the neck with a short lanyard ( lest said equipment gets dropped on the ground, in the toilet, or otherwise lost.) Those of the species that have learned to use a computer keyboard to bash out a short email to their buddies, will require special equipment. Due to the precarious nature of their nervous system, neanderthals have poor hand/eye coordination and are infamous for dripping, drooling, crumbling and otherwise making a giant mess while eating. They are also prone to spilling liquids. Keyboards must be encapsulated in a water tight rubber membrane. Such construction allows the entire assembly to be hosed down after use (in fact it is a good idea to design work areas so they can be hosed down after each use.) Also, keyboard constructed of stainless steel or titanium can extend the life of said equipment should the neanderthal feel the need to kill a cocroach, spider, ant or any other living creature scurrying across his desk.