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