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)(11,12)(13,17)(14,16)(15,19)(18,20)(21,23)(22,24)(25,26,30,29)(27,31,35,32)(28,36,38,33)(34,40,37,39)(1,3,5,8)(2,6,4,7)(9,11)(10,15)(12,16)(13,18)(14,19)(17,22)(20,23)(21,24)(25,27)(26,31)(28,34)(29,32)(30,35)(33,39)(36,40)(37,38)(10,16)(12,15)(17,23)(20,22)(25,27,30,35)(26,32,29,31)(28,37,38,34)(33,39,36,40)(1,2,5,4)(3,6,8,7)(9,12,14,15)(10,11,16,19)(13,20,21,22)(17,18,23,24)(25,27)(26,32)(28,34)(29,31)(30,35)(33,40)(36,39)(37,38)(9,11)(10,15)(12,16)(13,18)(14,19)(17,22)(20,23)(21,24)(25,28)(26,33)(27,34)(29,36)(30,38)(31,39)(32,40)(35,37) involution — undirected(1,4,5,2)(3,7,8,6)(9,13,14,21)(10,17,16,23)(11,18,19,24)(12,20,15,22)(25,29,30,26)(27,31,35,32)(28,33,38,36)(34,40,37,39)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.