Huh ok
We as Christians have the Holy Spirit inside of us, we just ask Jesus to give us.
As a friend, just say there is no need to you to do this, as Jesus Holy Spirit is way more powerful and wiser than anything occult. Light shines out the darkness. So...we don't need to place ourselves under a bushel.
There is a passage in the Bible about this in the book of Acts, a girl was divining a spirit, (and making a lot of money by fortune telling) the apostles cast it out of her in Jesus Name.
Check out Acts 16:16-18
There was also the incident of the riot that broke out after Paul preached against the idol cult of goddess Diana in Acts 19. Looks like it was resolved in court.
I don't have an answer to your problem, but as you concerned about your friend, just show him a BETTER way and he may follow. Those that were willing, actually burned all their idols and occult paraphenalia to show they didn't need them anymore. And it might have costs a lot of money (idolatry isn't cheap!!) but they did that so others won't fall into that trap.
Check your own life first. Is there any idols in your life, or dolls or what not that you spend a heap of money on? They might be 'good luck charms' or whatever. You don't need them, if you have any get rid of them. Encourage your friend also. Maybe your friend isn't strong enough in his faith to say no but you can - be a good influence. If he still persists than it might be a deal breaker for your friendship...I have had several friends before being born again that were involved in occults and I just had to not hang round them anymore because they just kept going on about it and trying to lure me in.
I remember one girl, a professed Christian, actually wanted to do my horoscope and sort of was pushing it on me, plus I knew she wouldn't listen to me, so I just had to stay away, and ask God to reach her. She was consulting them because lots of women do that to try and find their soul-mate or want control over their love-lives. Thinking 'oh if our stars are aligned' then it was fate or destiny or something like that. Then they have all these love potions and charms and wot not. Well, I don't need that. Love of my life is God.
You know, I get that people are interested in astrology or astronomy and what not. But God created the stars, and He has his purposes for them. Plus..a lot of things like horoscopes mostly is just made up anyway. It just tells you either what you want to hear, or asks you to give money to avoid a tragic fate, and there will always be people trying to predict tragic fates...I guess it makes them feel better when they come 'true' and then they can say they prophesised correctly. It's so stupid.