Another way of contacting God in Islam is dua’a (supplication or invocation). God says in the Qur’an:
{And when my servants ask you concerning me, [tell them] I am indeed near. I respond to the invocation of the supplicant when he calls.} [Al-Baqarah 2:187]
And:
{And your lord said, invoke me and I will respond to your invocation.} [Ghafir 40:60]
The Prophet Muhammad also confirms this fact of the communication that takes place between God and His servant during supplication by saying:
The Prophet has given us many tips of recommended times during which the communication between the believer and his Lord becomes closer and therefore his supplication becomes more powerful.
Communication with God takes different procedures from one religion to another. In Christianity, for example, it is imperative to reach God through a cleric mediator or a go-between of the holy order.
For instance, in Catholicism, the confession should be made at the hand of a priest and one cannot be entitled a Christian unless one is baptized at the hand of a cleric, and so on. But in Islam, the situation is different. No one is authorized to mediate between God and His servants. It is enough for any wrong doer to stand alone asking Allah's forgiveness and be sure Allah will respond.
Allah says in His Book:
{And those who, when they have committed sin or wronged themselves with evil, remember Allah and ask forgiveness for their sins; - and none can forgive sins but Allah.} [Aal Imran 2:135]
Source: http://english.tebyan.net/