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