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