I’tikaf means staying in the mosque for a specific purpose, which is to worship Allah for a certain number of days in accordance with the believer's own wish. It is prescribed in Islam and is mustahabb (recommended) according to the consensus of the scholars.

The time for I'tikaf could be anytime when one is allowed to fast. The best time is the month of Ramadan, especially, the last ten days.

Itikaf offers an immense hidden benefit, which is protection from the effects of excessive socializing. Itikaf also offers protection from the evil consequences of talking and sleeping too much, because a person usually does Itikaf on his own, turning to Allah by praying Qiyamul-Layl (Night prayers), reading Quran, making Dhikr, reciting dua, and so on.

But how to make the itikaf more attractive and useful?

Dr. Jamal  Badawi from European Council for Fatwa & Research give 5 tips to answer those questions:

1. First, to have the intention of worship.

2. Secondly, it is useful to have a group 'itikaf so as to encourage one another.

3.Also to learn from one another.

4. Make sure that there is enough food provision brought to participants so as that they may concentrate on prayer, recitation of the Qur'an and learning hadith and other useful knowledge.

5. Set a realistic goal for 'itikaf that suits the circumstances of at least most participants. To include inspiring talks as part of the 'itikaf program.

Reference: Islamonline.net