One vertex per element, one color per generator, with an edge from x to x·s.
(1,2) involution — undirected(7,8,12,16,13,18,11,17)(9,19,22,30,23,29,21,14)(10,24,25,32,26,31,27,15)(20,28,34,37,35,38,36,33)(3,4)(5,6)(7,9,11,21,13,23,12,22)(8,14,16,19,18,30,17,29)(10,20,25,34,26,35,27,36)(15,28,31,33,32,38,24,37)(4,6)(7,10,11,25,13,26,12,27)(8,15,16,31,18,32,17,24)(9,20,21,34,23,35,22,36)(14,28,19,33,30,38,29,37)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.