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