gistfile1.txt

    NSURL *url = <your url>;
    NSURL *fileUrl = <url to file on the local system>
    
    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
    [manager.requestSerializer setValue: self.accessToken forHTTPHeaderField:@"AccessToken"];
    
    [manager POST: url.absoluteString parameters:nil constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
        NSError *error;
        [formData appendPartWithFileURL: fileUrl name:@"upload" error: &error];
        NSLog(@"Error: %@", error);
    } success:^(AFHTTPRequestOperation *operation, id responseObject) {
        NSLog(@"Success: %@", responseObject);
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"Error: %@", error);
    }];