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