Invocation has its proper manners. Ibn ‘Āṭṭā’ Allah as-Sakandarī said:
Invocation has pillars, wings, means and appointed times. When it agrees with its pillars, it becomes strong. When it suits its wings, it flies in the sky. When it concurs with its prescribed times, it wins. When it corresponds to its means, it earns success. Its pillars are the presence of the heart, compassion, submission and humility. Its wings are sincerity. Its prescribed times are the early hours of dawn. Its means are aṣ-Ṣalāt ‘alā Rassūlillāh, that is, asking God to shed His blessings upon Muhammad (God bless him and give him peace).