The Prophet (may the peace and blessings of Allah be upon him) used to begin recitation by saying:
Transliteration: "Bismillaah ir-Raḥmaan ir-Raḥeem."
Translation: "In the name of Allah, the Most Merciful, Bestower of Mercy"
It is permissible to read this out loud or silently. However due to the large amount of evidence for reading it quietly, it can be said that it is better to read it quietly, so that only the person praying can hear.