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