This little script sets up a custom domain in MAMP and your hosts file.

vhost

#!/bin/bash

RED="\033[0;31m"
YELLOW="\033[33m"
REDBG="\033[0;41m"
BLACKBG="\033[0;40m"
WHITE="\033[1;37m"
NC="\033[0m"

mkdir -p /Applications/MAMP/Library/vhosts;
mkdir -p /Applications/MAMP/Library/vhosts/domains;

if [ "$1" ] || [ "$2" ]; then

  DOMAIN=$1;
  DOCUMENTROOT=$2

  # Add vhost
  touch /Applications/MAMP/Library/vhosts/domains/$domain;

  echo "<VirtualHost *>
    DocumentRoot "$DOCUMENTROOT"
    ServerName $DOMAIN
    <Directory "$DOCUMENTROOT">
        Options All
        AllowOverride All
        Order allow,deny
        Allow from all
    </Directory>
</VirtualHost>" >> /Applications/MAMP/Library/vhosts/domains/$DOMAIN;

  echo "127.0.0.1 $DOMAIN" >> /etc/hosts;

  # Restart MAMP
  /Applications/MAMP/bin/apache2/bin/apachectl restart;

  # echo out the domain name and copy domain to clipboard
  echo -e "Finished. ${BLACKBG}${WHITE} $DOMAIN ${NC} has been copied to your clipboard.";
  echo "$DOMAIN" | pbcopy;
fi

if [ "$1" = "remove" ] || [ "$1" = "delete" ]; then
    echo -e "${RED}Here are the current custom local domains:${NC}"
    for file in /Applications/MAMP/Library/vhosts/domains/*
    do
      if [ -f "$file" ];then
       echo -e "${YELLOW}${file##/*/}${NC}"
      fi
    done
    echo -e "${RED}Enter the site name you wish to remove:${NC}"
    read siteName;

    sed -i.bak "/$siteName/d" /etc/hosts;
    rm /Applications/MAMP/Library/vhosts/domains/$siteName;

    echo -e "${YELLOW}$siteName removed."
fi

MAMP Virtual Host Creation Script

1. Download the script & cd to it
2. chmod +x ./vhost
3. mv ./vhost /usr/local/bin
4. subl /Applications/MAMP/conf/apache/httpd.conf and add the following line at the end of the file:

Include vhosts/*

Then, to use:

$ vhost wildebeest.dev ~/sites/wildebeest/wildebeest

That should be it. Open wildebeest.dev in your browser and confirm it's working.