You can get there in many ways, but the best one is to choose an eastern exit from Paradise Survival Camp what takes you to a bigger path where the car is parked. You can defeat nearby zombies or ignore them and focus on getting to the car ASAP.
As you get inside the vehicle, ride to southern-east, staying at the main road and trying to ram zombies (easy XP). On your way you pass among others Kiwi Camp which is connected with one of side quests.
Road will turn northern-east. I recommend to stay on the main path and stop only when you get to a Hoyahoya Bar, shown on the screen above.
Get out of the car and choose path on east, leading to Halai Village. You should meet only Walkers and Infested. If you run at some Thug, Suicider or Drowner, keep him at bay and avoid confrontation.
When you enter the village, move southern-east and remember to look around carefully, so the zombies won't surprise you. You goal is marked on the screen - it's a fenced camp. Approach the gate and talk with Jackson. He won't let you in but tell about a nearby harbor where maybe you'll find some boats.
The harbor is on the northern-east from the fishing village. If you want to get there on your feet, go there, avoiding stronger zombies. You should get onto a path leading to lianas.
Continue walking to a harbor, choose eastern path on crossroads what takes you to a lower enter of Marik's Marina.
If you don't want to risk with going on feet, return to your car. Enter it ad head north, after few moments turn east, you'll pass Zimakani Rest Camping.
Head east, staying on the main road. Soon you'll arrive at main gate to Marika's Marine. Listen to what Harlow has to said and get new objectives.