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