Après avoir effectué le paiement, veuillez me prevenir afin que je puisse organiser la suite de la procédure. Je vous remercie cordialement.
This is what I would write. Of course, I don't know the context nor who it is addressed to. Nevertheless, this tone is formal and polite.
C'est correct? ma phrase? I want to say" Pls inform me after you arrange payment, so that I can do the next arrangement accordingly". Merci!