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