Still on the rules and conditions for Itikaf,  it is better to begin I`tikaf on the eve of the 20th of Ramadan at sunset until the sighting of the moon for `Edul-Fitr for those who intended it for the ten days. 

Otherwise, you can start at sunset any of the days depending on the number of days you intend to observe seclusion. This means those who have not gone into Itikaf now can still make it. 

During I`tikaf men should stay in the Masjid day and night, and should not leave it except to use the toilet or shower. They are also allowed to eat inside the Masjid, but if it is not convenient they may go outside to eat and come back as soon as they finish within a close distance. 

But thank God, most mosques now have facilities for the convenience and comfort of the Mutakif. During I`tikaf one should spend most of the time in prayer, reading the Qur’an, dhikr, and reflection. Engaging in business and other worldly conversation and activities is not allowed during I`tikaf. 

However, attending a Janazah (Funeral), visiting a sick person or leaving for any emergency is permissible. While in the masjid for Itikaf, it is also recommended that the mutakif keeps himself busy with prayers, reading  the Holy Quran, engage in zhikr and should avoid all kinds of worldly things. 

It is also recommended for those who know the Holy Quran to teach it during their Itikaf. It is one of good deeds during seclusion. There are records of the Prophet doing that during Itikaf as well as his companions.

The Mutakif should refrain from talking too much or chatting away time. You can be involved in brief discussion with people and also issues regarding the Itikaf and worship of Allah. In the course of your discussion with people, you have to avoid argument, disputes and speaking in hateful manners. 

You also attend to your visitors especially family members who intend to pass useful and urgent information, but must be very careful in taking your time for ibadah, you should rather concentrate and devote your time to acts of worship.

May Allah make it easy for us. Amin. Enjoy your Ramadan!