What about praying to Lucifer?
I see it as a choice but the best way to communicate with him is by talking to him. Talk to him like if you were having a conversation with him. You may be not be able to see or hear him but he will hear what you are saying.
I know that some believe that praying to him should be a requirement but in this path, it is nothing like what god wants from his followers. Lucifer would not require you to pray to him, to worship him, or even giving your soul to him. He would not want to ask you to give him your soul. We are not his slaves and nor does he want slaves. His main goal is to help many liberate themselves from god’s slavery and help remove themselves from god’s dominion.