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