From Singapore, other than taking the conventiaonal route via the JB causeway towards Kukup (Pontian), there is another route if you are taking public transportation, that is going through Second Link (Linkedua), Tuas.
以马新第二通道的公交简略描述如下：Summary of the public transportation route (via secondlink) as below:
裕廊东地铁站Jurong East MRT-> 新加坡海关 Singapore Custom 〉马来西亚海关Malaysia Custom〉振林山 Gelang Patah> 笨珍 Pontian > 龟咯 Kukup
Jurong East MRT bus interchange 裕廊东地铁站巴士转换站
注1：从新加坡关卡至马来西亚关卡，只要是causeway link 公司的巴士都可以上车，
P/S1: You can board any Causeway Link buses
from Singapore Custom heading towards Malaysia Custom, be it the same
bus you took from Jurong East MRT or originated from Boon Lay MRT, as
all will still to alight at Malaysian Custom for
clearance.
注2：在马来西亚关卡办理入境手续后，
P/S 2: Do take note to board on the CW4
Causeway Link bound for Gelang Patah , which normally parked at the
first bus bay in front of the convenience shop. It's always a good idea
to ask double check with the bus driver or the Causeway
Link worker ("Gelang Patah") before boarding on the bus. Sometime bus
parked outside the shelter, due to other buses occupancy of the lane.
Interior of Causeway Link Bus (@Gelang Patah) 巴士内观 (摄于振林山）
注3：振林山往笨珍的causeway link 巴士号码为52T，车费为马币4.20,
P/S 3: Take the Causeway Link bus 52T from Gelang Patah to Pontian. Due to the fact that this route is not a popular route, thus there is only a bus arranged to back and flo Gelang Patah and Pontian. So you will have to wait for 2 or 3 hours if you miss the bus (For weekend, will be 2 hours for the next trip except lunch hour-3 hours). For detail bus time table, please visit their website for details.
注4：如果错过了52T巴士，只能乘搭德士，不过你有2个选择：
P/S 4: If you do miss the 52T bus, the only
option for you is the taxi. But you do have 2 options in taxi - budget
or the convenient way. For budget mode, take taxi to Pekan Nanas, and
board any bus towards Pontian (Normally it's Maju
96 bus from Larkin, RM2 from Pekan Nanas to Pontian); For convenience,
take the taxi straight to Pontian or Kukup ! Taxi fare from Gelang Patah
to Pekan Nanas RM 25, while going Pontian cost RM40 to 50, drivers will
not use the meter, so beware being quoted
high)
纵然该条是使用马新第2通道的行程，似乎比直接使用长堤（Larkin巴士站），显得比较曲折、得准备马币零钱，52T不找零。但我个人觉得马新第2通道会比较顺畅省时间，如果掌握好52T的时刻表（除了佳节连假）。
Even though going to Kukup via the second link (Gelang Patah) is more complexed and you will be troubled have to prepare the small change in Ringgit (bus driver does not give the change) . But my personal opinion is commute via secondlink tends to save the time and traffic smoother provided you able to catch the 52T bus (exceptional during long weekend or school holiday)
