Nelson's Illustrated Bible Dictionary sums astrology in the following manner:
"The Bible's contempt for astrology is most clearly seen in its prohibition of any technique to aid in predicting the future. Astrology assumes that God does not control history. It assumes that history is governed by the affairs of the pagan gods as revealed in the movement of the planets. The believer knows that a sovereign God rules this world. He also knows that resorting to astrology is a denial of the life of faith by which one trusts God and not his lucky stars for the future."

5. Even if the Bible does condemn these things why should that bother me? These practices should bother the Christian a lot. God speaks strongly against these things and he disciplines those whom he loves Heb.12:6. Also the Christian should consider what Jesus said in  Luke 6:46 "And why do you call Me, 'Lord, Lord,' and do not do what I say?"

As far as the non-Christian, all I can say is the fear of the LORD is the beginning of wisdom Ps 111:10. Apart from Jesus Christ a person goes to hell. Even one sin in your whole life will keep you out of heaven without acceptance of Jesus and his atoning sacrifice. I suppose if you want to follow astrology and other such things rather than God, you can. If you are already rejecting Jesus Christ, what difference does it make if you are involved in these things? Apart from Jesus you will be spending eternity in hell anyway.
I believe it would be much wiser though to repent and turn to the Lord.