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