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