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