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