Intent intentNotif = new Intent(context,StartActivity.class);
        PendingIntent pIntent =
PendingIntent.getActivity(context,0,intentNotif,0);
notification = createNotification(
                "Text1",
                "Text2",context,pIntent);
am = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
        am.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis()+5000,10000,pIntent);
        manager.notify(NOTIFICATION_ID,notification);

Вот сам метод для создания уведомления
public static Notification createNotification(String content, String title, Context context, PendingIntent pIntent) {
        NotificationCompat.Builder builder = new NotificationCompat.Builder(context);
        builder.setContentIntent(pIntent);
        builder.setWhen(System.currentTimeMillis());
        builder.setSmallIcon(R.drawable.my_goal_image);
        builder.setTicker("Be better");
        builder.setAutoCancel(true);
        builder.setContentTitle(title);
        builder.setContentText(content);

        return builder.build();
    }