curl get.pow.cx/uninstall.sh | sh
echo 'export POW_DST_PORT=88' >> ~/.powconfig
curl get.pow.cx | sh
Now, open MAMP Pro, create a new host. Doesn't matter what it is named and which directory is selected (though I use 'rails.dev' and the folder I keep my Rails apps in).Also, deselect the select box for "local name resolution", just in case. Then go to the Advanced tab, and fill this in to the textarea labeled "Customized virtual host general settings":
ServerName pow
ServerAlias *.dev
ProxyPass / http://localhost:20559/
ProxyPassReverse / http://localhost:20559/
ProxyPreserveHost On
Resource from imdefr.com