Hummus wrote:

Imagine you're out alone, say on a bus or a train and a stranger comes up to you, whose possibly not a Muslim, and they ask you to define Islam, what would you say to them?

start of with belief in allah and his messenger saw describe allah then muhammad saw and the other prophets as like isa as ibrahim as nuh as musa as

and then tell the the definition of islam and what islam consider right and wrong in todays case clear up terrorism and jihad controversy

There is no god but God and Muhammad is his messenger - as well as the other prophets.

Then mention the rest of the main articles of faith - in the holy books, angels, life after death; day of judgment day/hell and heaven, predestination

Funny you brought this up actually.

My mate was talking to my other non-Muslim mate about general stuff today, and from a conversation about make-up, it came down to religion, suprisingly. 

So then I listened to what they had to discuss, and she said; ''I don't understand the point of Christianity, because its changed so much and doesn't make sense''. Then she went on to say how/why some girls wear headscarves and other's don't and how she doesn't think they are forced to wear one because otherwise everyone would if it was stressed upon by religion etc etc. I found it sweet when she said, ''I really like your religion''. 

From listening to what she had to say, it just made me feel ever so grateful in so many ways, and I really love how she just talked about it all like such a wise person.

(I know this was probably off-topic, but I just thought it'd be alright to share)

I think the appropriate way of defining Islam is through presenting yourself in the best way possible. But in terms of speech, stating the obvious is key, and detail follows.