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