Here is the following ways you can do to get out of new leaf city (:
1) Walk to the subway, just as what xiaopearl had said (:
2) Ask Gm to warp you, code to henesy, map ID: 100000000
3) Press the little icon TRADE beside your menu and warp to FM. You need to pay
1000 mesos to Spinel to fly away to other places (:
i hope this helps (: