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