Yes, some people have trouble with visualization, my dear. This is normal. It is through practice that you will get better and better at it. Just keep going on and do your best. Be consistent with meditation.
You say you are new. Okay, so just go little by little. I know how overwhelming it is. Sometimes I feel like learning and reading, going through the process is a never ending task. Guess what? it is certainly a never ending task. There is always much much work to do, a lot ahead of you and it is important that you do your journey in the correct order, that is, start with the beginners meditations, then proceed with the intermediate and finally the advanced.
When do you know that you can move forward? Just trust your common sense and do not rush anything, you will know when it is time to move onto new things. Know that everyone is individual, that is, some of us can progress faster than others, but that is something our of your reach because it comes from your previous lives, as stated in the JoS site.
Just be patient, be happy and know that Father and the Gods are with you all the way, as wonderful Marchosias is with you now.
I hope I have been of little help, my friend.
HAIL FATHER SATAN FOREVER!
Anyone able to guide me?