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