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