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