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