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