Create a venv 
`python -m venv .venv`

Activate the venv
`. .vent/bin/activate`

Install the dependencies
`pip install -r requirements.txt`

You will potentially need more tooling to create the bitstream and flash the bitstream for the specific FPGA. In my case I'm working with an IceBreaker. So I've installed the `nextpnr-ice40` toolchain. Yosys is builtin to amaranth, that is why I'm running it within an venv to ensure it doesn't mess with system installed packages.