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)(13,14,16,17)(15,19,20,18)(23,26)(24,28)(5,7,9,8)(6,10,12,11)(14,17)(18,19)(21,22,25,27)(23,24,26,28)(5,7,9,8)(6,11,12,10)(13,14)(15,18)(16,17)(19,20)(21,23,25,26)(22,24,27,28)(1,2)(3,4)(5,8,9,7)(6,11,12,10)(13,15,16,20)(14,18,17,19)(5,6)(7,11)(8,10)(9,12)(13,14)(15,19)(16,17)(18,20)(21,24)(22,26)(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.