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