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