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