I find the most effective (in my experience) way to describe the 'technical' side of MS is to use the imagery of electrical wires with the plastic coating on them (to mimic the nerve in an MS patient).

People begin to 'get it' when you tell them that MS can affect the central nervous system as a whole (and most folk I meet don't fully understand the CNS either - I tell them, everything from the senses to mobility - walking, for example).

Then I explain the process of the disease eating away at the myelin sheath on the nerve like taking a knife and peeling back the plastic protective coating from the electrical wire. What happens when you expose bare wire running a current? Many bad things - and most people at this point have the 'ah HA!'.

If they really want to know how it affects me personally, I tell them "I'm very fortunate that I am not affected with my mobility and cognitive thoughts. I went for years thinking I just had a very bad migraine or headache". Which is the truth. I am very fortunate, but I too make it a point to explain that everyone with MS is like a fingerprint - completely unique from one another and with their disease course.