The month of Ramadan is the best month of the year, because Allah has chosen it to make fasting this month obligatory and the fourth pillar of Islam and He has prescribed for the Muslims to spend its nights in prayer, as the Prophet (peace and blessings of Allah be upon him) said:
“Islam is built on five (pillars): testimony that there is no god but Allah and that Muhammad is the Messenger of Allah, establishing prayer, paying zakah, fasting Ramadan and performing pilgrimage to the House (Ka’bah).” [Agreed upon]
And he (peace and blessings of Allah be upon him) said:
“Whoever spend the nights of Ramadan in prayer out of faith and in the hope of reward, his previous sins will be forgiven.” [Agreed upon]
I do not know of any specific way of welcoming Ramadan, but the Muslim should welcome it with joy and happiness and thanking Allah for enabling him to reach Ramadan, for He has caused him to be among the living who compete in doing righteous deeds. Reaching Ramadan is a great blessing from Allah. Hence the Prophet (peace and blessings of Allah be upon him) used to give his companions the glad tidings of the arrival of Ramadan and explain its virtues, and the great reward that Allah has prepared for those who fast and who spend the night in prayer. It is prescribed for the Muslim to welcome this blessed month with sincere repentance and preparations to fast and pray qiyaam, with a sound intention and sincere resolve. End quote.
Source: Majmoo’ Fataawa wa Maqaalaat Mutanawwi’ah (15/9)