One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6,9,11)(7,12,8,10)(13,14,19,21)(15,22,16,20)(17,23,27,26)(18,24,28,25)(5,7,9,8)(6,10,11,12)(13,15,19,16)(14,20,21,22)(17,25,27,24)(18,23,28,26)(2,4)(5,6)(7,10)(8,12)(9,11)(14,21)(15,16)(23,26)(24,25) involution — undirected(1,2)(3,4)(5,8,9,7)(6,10,11,12)(13,16,19,15)(14,22,21,20)(17,24,27,25)(18,26,28,23)(13,17)(14,23)(15,25)(16,24)(18,22)(19,27)(20,28)(21,26) involution — undirected(13,18)(14,24)(15,23)(16,26)(17,20)(19,28)(21,25)(22,27) involution — undirectedA 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.