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