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