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