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