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