I use a remote mail facility. There are a bunch of them. Mailboxes etc, UPS store, and that kind.
They cost about 100 US dollars a year and they will sign for packages.
However, if the law picks your package to bust, it doesn't make a rats ass where you have them sent. If the payment is tracked back to you, or you just touch the package, you're busted.
In the USA, if they bust you with a felony for using US mail to have an illegal delivery, they can easily get a search warrant for your house. When they bust you at the post box, another team will already be inside your house ripping it apart.
There is no absolute safe way. Getting busted comes with the territory of growing your own weed. The possibility will always be there.
If you can't stand the heat, stay out of the kitchen.
It's a damn shame, but that's the current way of the world.
Good luck to you man.