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)(11,16)(12,22)(13,15)(14,18)(17,23)(19,24)(20,21)(25,26)(27,29)(28,33)(30,35)(31,36)(32,34)(37,38)(39,40)(1,3,5,8)(2,6,4,7)(9,11)(10,16)(12,14)(13,20)(15,21)(17,24)(18,22)(19,23)(25,27,31,34)(26,32,36,29)(28,35,39,37)(30,33,38,40)(9,12,15,23)(10,17,13,22)(11,19,21,14)(16,18,20,24)(25,28)(26,33)(27,37)(29,38)(30,32)(31,39)(34,35)(36,40)(9,12)(10,17)(11,14)(13,22)(15,23)(16,24)(18,20)(19,21)(25,29,31,32)(26,34,36,27)(28,38,39,30)(33,35,40,37)(1,4,5,2)(3,7,8,6)(9,13,15,10)(11,20,21,16)(12,22,23,17)(14,18,19,24)(25,30,31,38)(26,35,36,37)(27,33,34,40)(28,32,39,29)(9,14)(10,18)(11,12)(13,24)(15,19)(16,22)(17,20)(21,23)(25,26)(27,32)(28,33)(29,34)(30,37)(31,36)(35,38)(39,40) involution — undirectedA 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.