What are the rulings concerning marriage (Nikah) in Islam, and how is an engagement (Khutbah) conducted according to Islamic principles?

"Whoever wishes to marry should supplicate [to Allah], and choose a spouse who is religious and of good character. He should propose to her through her guardian, and he is permitted to look at her. It is recommended to perform Salatul-Istikhara (prayer for guidance). Marriage has pillars and conditions, including the guardian and witnesses. The wedding feast (walima) is sunnah (definition), and announcing the marriage with a drum (duff) is also sunnah. It is recommended for the husband, upon consummating the marriage with his wife, to recite the traditional supplication. One must beware of romantic relationships outside of marriage, and it is obligatory to learn the Shariah rulings before undertaking any action."