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