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