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