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