It would be nice if would could all give each other advice and get some advice from previous applicants 
But anybody from any country can give advicee 
This forum is full of advice ā what kind do you need?
Hey 
Previous Nigerian applicant here. What kind of advice are you looking for?
Yo wassup homeboy. Watcha need?
Basiaclly test scores
If you took subject tests
Extra curricular stuff and everything
Just any advice really

I used Khan Academy for the SAT. Take practice tests as often as you can. I donāt have any advice for the subject tests since I murdered them. :))
Extracurriculars are posted in the āCan more graduated seniors do āactual resultsā threads?ā thread.
Start early. Do not procrastinate. Forget dream schools. Work hard on every aspect of the application. Get ready to be crushed, but also donāt lose hope. Craft your application like itās a movie. Would you want to see that movie? Make it cohesive and memorable. Donāt try to make your application like everyone elseās. Be brave.