Communicating with Spirit can be much like making a phone call.

Clear the line. Minimize behaviors that clog and 'fog' mind and body. Processed foods, alcohol, caffeine, tobacco & other toxic substances, loveless human interactions, meaningless sex, addictive behaviors, fear-based thoughts and actions create energetic debris and blockage. If you're unable to hear what God is saying, do a whole body cleanse. Make it realistic, one you can commit to and complete. Stay hydrated, as water is an energy conductor and is a currency for accessing the higher-self.
Dial the number. Ask Spirit what she wants you to know, or ask what you want to know. Tell him you're ready to hear. Welcome Divine into your world during sleep and waking hours. Open your heart to receive any and all messages that are meant for you.
Listen. HELLO?! Pay attention to the vibrations around you. Journal. Record your dreams. Listen for repeated lyrical themes in songs on the radio. Write it down when you feel a flip in your gut or a pulsation in your forehead. Watch for synchronicities and the recurrence of certain numbers or colors, finding pennies or feathers on the ground. Don't ignore strangers who say things to you -- even if you think they're off balance. Sometimes, these people are mitigating psychic phenomena that they don't understand that's what makes them behave 'oddly.' Hear the words and see if they resonate with you. What you do with the information you receive is up to you.