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