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