Home grown turntable platform/base?

I picked up a used Pro-Ject Debut Carbon turntable for the family room. We are not big into vinyl, mostly listen to digital, but my 16yo daughter has shown an interest in getting some records. I’m getting excited about her interest in vinyl and audio. What is a good platform material to use? Wood? Granite? Should I add sorbothane and/or spikes underneath? I’m not looking to spend a lot but feel I should have some decent isolation for it. The turntable currently sits on a hollow shelf. It’s where it has to be so I need to make this work.

Thanks for any input.