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