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