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