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