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