What gear does Gabrielle Nistico recommend for noise reduction in recording studios?

I focus less on fancy gear and more on smart acoustic treatment you can DIY cheaply.

From my content on “soundproofing,” I recommend:

1. Using pillows, blankets, mattress toppers, and couch cushions to absorb reflections in a small space or closet
2. Moving blankets or quilts tacked or Velcro’d to walls
3. Carpet padding/remnants on walls for dense, ugly-but-effective absorption, then covered with fabric you like

Are you treating a closet, a corner of a room, or building a small booth?