After shooting down the 'urban E&E' thread as dangerous fantasy, I'm a bit reluctant to give this information.
But here goes anyway:
When we did Escape and Evasion exercises we were trained to coat matches in wax and slip them inside clothing seams. One thing about matches; they are the smallest fire making method.
It didn't work of course; the platoons doing the hunting for us had had the same training. They simply took all our equipment and clothes and gave us new ones. Maybe it would be helpful if you were travelling in the middle east or somewhere being held prisoner by amateurs is a possibility. Concealment equals guilt in LE eyes; so I'd avoid it anywhere civilised.
The Sock