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