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