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