I personally don't use the Necronomicon and honestly I don't recommend it. And I don't like it, despite it genuinely having Satanic knowledge and meditations based upon it.
There's a couple JoS pages you should read. I think most have been mentioned and probably will have been since this will be posted.
I actually also recommend HPCobra's 40 day meditation program because it will help build foundational meditation skills necessary to complete the opening of the chakras. It's in the beginner sticky/pinned thread.
Opening:
https://joyofsatan.org/www.angelfire.com/empire/serpentis666/OpeningChakras.html
This will take some time. You should note certain chakras take several days if not weeks. I am still in the process of it myself. I started when I began Satanism, but I did not end up finishing out of laziness and lack of routine. Perhaps consider getting a cheap diary, using your phone or marking on a piece of paper to remind yourself to meditate. If you have little time you can do it in the shower before work etc. You should also know that things may happen you don't like (whispers and visions of things trying to cause trouble/fear/anxiety), so master
void meditation as well.
Hands, feet hip and shoulders should be done too. I can feel more energy flow in my body after I have done this.
Correct pronounciation/finding chakra tune:
https://joyofsatan.org/www.angelfire.com/empire/serpentis666/Tuning.html
I have not attempted this but I think it's important so I'll put it here
Unblocking chakras:
https://joyofsatan.org/www.angelfire.com/empire/serpentis666/Open_Blocked_Chakras.html
If you feel like you're having particular trouble with a particular chakra. I have had trouble with my heart and throat chakra. Also consider doing yoga to help chakra flow, you will feel it open right up.
Proper Alignment: https://joyofsatan.org/www.angelfire.com/empire/serpentis666/Chakra_Alignment.html
This took me a couple goes as it can be tricky and disorientating. They are not all the same direction and the flow is explained through each one. You might even gain your own understanding on this too.
Clairvoyance:
https://joyofsatan.org/www.angelfire.com/empire/serpentis666/Clairvoyance_Points.html
Clairaudiance:
https://joyofsatan.org/www.angelfire.com/empire/serpentis666/Psychic_Centers.html
I am trying to perfect these myself as I am near desperate to have these abilities. Separating delusion from reality can be hard. You may even find you begin to smell things.
Chakra Spin:
https://joyofsatan.org/www.angelfire.com/empire/serpentis666/EZ_Chakra_Spin.html
This is great for a quick refresher if you're feeling rusty. I use tibetan singing bowls with this because it has a circular spinning sound/frequency and a pure sound which makes it easy to visualise.
Full Chakra meditation:
https://joyofsatan.org/www.angelfire.com/empire/serpentis666/Full_Meditation.html
This should not be done until you have opened your chakras. I am not sure what this does as I have not opened my soul fully yet but I'm sure it will come in handy and I'm excited to try it eventually.
Chakra sounds:
https://joyofsatan.org/www.angelfire.com/empire/serpentis666/Chakra_Sounds_Meditation.html
I have not done this personally but again I am excited to try.
Please ask us any more questions you might have. Otherwise good luck!