Alister Doyle, Noodle Advisor
You should check out the International Education Financial Aid website's Scholarship Search. It lets you browse awards based on what you want to study, where you want to study and where you're from. And there are actually a couple of scholarships specifically for people in Cameroon who want to study in the US, such as the Ishe Komborera Africa Award.
You should also try using our new Grad School Search to find out what schools have psychology programs that match your interest. You can refine your search by location and concentration and you can then contact the Admissions Office at each of these schools if you have any specific questions. Best of luck!