One vertex per element, one color per generator, with an edge from x to x·s.
(1,2) involution — undirected(3,4)(5,7)(6,9)(8,10)(11,12)(13,19,21,16)(14,22)(15,18)(17,23)(20,24,26,25)(27,28,30,33,31,34,37,40)(29,32,36,39,35,38,41,42)(4,7)(5,10)(8,9)(11,13,15,21)(12,16,18,19)(14,20,23,26)(17,24,22,25)(27,29)(28,32)(30,36)(31,35)(33,39)(34,38)(37,41)(40,42)(11,14,15,23)(12,17,18,22)(13,20,21,26)(16,24,19,25)(29,35)(32,38)(36,41)(39,42)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.