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