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