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