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