Update docker installation guides

README.md

@@ -84,25 +84,31 @@ See [CONTRIBUTING.md](CONTRIBUTING.md)
 
 You should have installed Docker and Docker Compose in your machine.
 
-On macos just:
+#### Macos
 
 ```bash
 brew install docker
 brew install docker-compose
 brew cask install docker
+open -a docker
 ```
 
-On linux:
+You'll be asked to give Docker app permissions and type your password, then you're set.
+
+#### Linux
+
+1. Install Docker:
 ```bash
-# Install Docker
 sudo apt-get update
 sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
 sudo apt-add-repository 'deb https://apt.dockerproject.org/repo ubuntu-xenial main'
 sudo apt-get update
 apt-cache policy docker-engine
 sudo apt-get install -y docker-engine
+```
 
-# Install Docker Compose
+2. Install Docker Compose
+```bash
 sudo curl -o /usr/local/bin/docker-compose -L "https://github.com/docker/compose/releases/download/1.15.0/docker-compose-$(uname -s)-$(uname -m)"
 sudo chmod +x /usr/local/bin/docker-compose
 ```