This step will allow you to run a Hyperledger Fabric runtime locally and deploy your business networks:

1. Choose a directory, such as ~/fabric-dev-servers.
2. Now get the .tar.gz file, which contains the tools for installing Hyperledger Fabric:

mkdir ~/fabric-dev-servers && cd ~/fabric-dev-servers

curl -O https://raw.githubusercontent.com/hyperledger/composer-tools/master/packages/fabric-dev-servers/fabric-dev-servers.tar.gz
tar -xvf fabric-dev-servers.tar.gz

You've downloaded some scripts that will allow the installation of a local Hyperledger Fabric v1.2 runtime.

3. To download the actual environment Docker images, run the following commands in your user home directory:

cd ~/fabric-dev-servers
export FABRIC_VERSION=hlfv12
./downloadFabric.sh

Well done! Now you have everything required for a typical developer environment.