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