For Step 2 of the Jeans example
What is the meaning of a sign?  In the first part of the table translate the signs into words. Now in the last part define a sign that identifies the words. Having got a sense, identify key words for your topic and define their signs.

Sign / symbol	Meaning / word
	palm tree, oasis
	cactus, desert
	asteroid, danger
	world
	drop, water, oil
	crane, harbour
	arrow, means
	money
	potato
	cotton
	factory
	world trade