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