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