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