How to Increase Your Love for Prophet Muhammad
Question

How can one develop in their heart love for Prophet Muhammad more than anything else in the world?
Praise be to Allah.Why is it important to love the Prophet?

It increases faith: The strength of love for Prophet Muhammad (peace and blessings of Allah be upon him) is connected to the Muslim’s faith. When his faith increases, his love for the Prophet (peace and blessings of Allah be upon him) increases.
It is an act of obedience: Loving the Prophet (peace and blessings of Allah be upon him) is an act of obedience to Allah and a means of drawing closer to Him.
It is an obligation: Loving the Prophet (peace and blessings of Allah be upon him) is one of the obligatory duties in Islam. 

Anas said: The Prophet (peace and blessings of Allah be upon him) said: “None of you truly believes until I am more beloved to him than his father, his child and all the people.” (Narrated by Al-Bukhari, 15; Muslim, 44) 
How to Increase Our Love for Prophet Muhammad
You can increase your love of Prophet Muhammad  (peace and blessings of Allah be upon him) by realizing that: 

Prophet Muhammad was sent by his Lord Who chose him above all of creation to convey the religion of Allah to mankind. Allah chose him because He loved him and was pleased with him. If Allah were not pleased with him, He would not have chosen him. So we must love the one whom Allah loves and be pleased with the one with whom Allah is pleased. We must realize that he is the close friend (Khalil) of Allah and that close relationship is a higher status and it is the highest degree of love. 

Jundub said: I heard the Prophet (peace and blessings of Allah be upon him) say: “I declare before Allah that I have no close friend (Khalil) from among you. Allah has taken me as a close friend as he took Ibrahim as a close friend. If I were to have taken a close friend from among my Ummah, I would have taken Abu Bakr as a close friend.” (Narrated by Muslim, 532)

Allah has raised the status of Prophet Muhammad very high, for he (peace and blessings of Allah be upon him) is the best of mankind. 

Abu Hurayrah said: The Messenger of Allah (peace and blessings of Allah be upon him) said: “I will be the leader of mankind of the Day of Resurrection, the first whose grave will be opened, the first to intercede and the first to be asked to intercede.”  (Narrated by Muslim, 2278) 

He suffered trials and difficulties in order to bring Islam to us. We should remember that the Messenger (peace and blessings of Allah be upon him) was persecuted, hit, slandered and insulted; the closest people to him disowned him and accused him of being a madman, a liar and a sorcerer. He fought the people in order to protect the religion so that it could reach us; they fought him, expelled him from his people and homeland, and gathered armies against him.  
We should follow the example of his companions who loved him deeply. They loved him more than their wealth, children, and their own selves. There follow some examples of that: 

Anas said: “I saw the Messenger of Allah (peace and blessings of Allah be upon him) when the barber was cutting his hair and his companions were going around him wanting to ensure that his hair would fall only into someone’s hand.” (Narrated by Muslim, 2325) 
Anas (may Allah be pleased with him) said: “On the Day of Uhud some of the people fled and left the Prophet (peace and blessings of Allah be upon him), but Abu Talhah stood before him covering him with a shield. Abu Talhah was a powerful archer who broke two or three bows that day. When a man passed by carrying a quiver containing arrows, he would say: Give them to Abu Talhah. Whenever the Prophet (peace and blessings of Allah be upon him) raised his head to look at the people, Abu Talhah would say: O Prophet of Allah, may my father and my mother be sacrificed for you, do not raise your head lest you be struck by an arrow shot by the enemy. My neck is before your neck.” (Narrated by Al-Bukhari, 3600; Muslim, 1811) 

You should follow his Sunnah in word and deed, so that his Sunnah is the path you follow in your whole life, and you put his words before any other words and put his command before everything else; and you should follow the `Aqidah (belief) of his noble Companions, and the `Aqidah of the Tabi’in who followed them, and the `Aqidah of those who followed their path until the present day, namely Ahl al-Sunnah wal-Jama`ah, and avoid Bid’ah (religious innovation), especially the Rafidis (Shi`ah), for their hearts are hardened against the Messenger of Allah (peace and blessings of Allah be upon him) and they give their Imams precedence over him and love them more than they love him.  

We ask Allah to help us to love His Messenger (peace and blessings of Allah be upon him) and to make him dearer to us than our children, parents, families and our own selves. 
And Allah knows best.