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