If you’re making altered books or cards, you often use single, meaningful words.
I have found a good proposal on how to illustrate words.
On the picture I tried to put the word ‘Glass’ onto the photo of the tesselation as if it was made of glass (not bad for a first try? ;-))
My inspiration was a tutorial on how to create a gel button.
It was fun ;-)
Links:
Illustrate Words
Gel Button