What is the ruling on signaling with the left hand when greeting from afar, if the right hand is occupied?

The Sharia encourages the spreading of peace (salam) among Muslims verbally, as it is among the best deeds in Islam and was the first greeting for Adam (peace be upon him) and his descendants. A Muslim greets with his tongue and gestures with his right hand, or with his left if the right is not possible. The Sunnah is for a Muslim to greet his Muslim brother with the prescribed Islamic greeting: "Assalamu alaykum wa rahmatullahi wa barakatuh" (Peace be upon you, and the mercy of Allah, and His blessings). There is no harm in adding a hand gesture for someone far away, along with verbalizing the greeting. Similarly, there is no prohibition against saying "Hayyak Allah" (May Allah preserve you) or "Ahlan" (Welcome) after giving the prescribed Islamic greeting. However, restricting oneself to these phrases or greeting with a car horn is contrary to the Sunnah and must be abandoned.