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