You don't have to be too precise and visualize it in all its details, obviously if you try to force yourself to succeed as much as possible you will fail. Visualize as much as you can afford, plus if you do what you can, meditation will still work. Even if you are not 100% accurate in every detail (and in fact you don't have to be), you will get effects from your meditation.
Also know that things will come with time. Until a year ago I was unable to visualize any chakra at all other than a simple, poorly defined outline of them. I continued without letting this obstacle get me down and now I can visualize each chakra very well. Even spinning it at the speed of light, before I couldn't even get it to move without my viewing issues moving it upside down or ruining the image. Yet I repeat that they now all rotate at the speed of light as soon as I want them to.
A good trick is precisely to not commit too seriously to the visualization, but to let it happen by provoking it. With this trick I was also able to visualize light/energy over time. Something that a year ago I thought I would never be able to do, in fact I was sure of it. Yet you should see how each of my chakras lights up brightly.
If I managed it while I had 0% visualization and I had to look for images of colored pyramids on the internet to reproduce them in my mind and in any case it was impossible for me, I believe that over time it will be a goal within everyone's reach. I can't give you better advice than this.