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