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