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