Honestly it’s nearly impossible to quiet down a 2 stroke engine all the way, but there are a few aftermarket silencers you can buy that enables you to install more packing inside of them.
Another thing to consider is: If you’re running a K&N filter, then remove it and install an air box ( this will quiet it down a bit)
I understand that free is good, but I highly recommend a race track, that way you can have more fun, and open it up as much as you want to.
Of course if you have a track near you, but that’s just my 2 cents. Good luck and have fun, while keeping it safe. Fast Freddy.