Hi. As I live in an apartment, practicing the trumpet is a very difficult thing to do if you care about your neighbours' well-being
For practicing drills, I have taken an unwanted dirty clothes basket. Then I put cushions and pillows and towels all around is and inside. Then I put my bell inside it and play into it. I put the basket on it's side in my cupboard on top of some chest of drawers. This dampens the sound a lot compared to nothing at all. I still suspect however that some noise carries.