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