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