If you don’t already have an .htaccess file in the root of your domain, create one and add the following code. If you already have an .htaccess file, add the following code in front of everything that might be in there
RewriteEngine On
# Add all the IP addresses of people that are helping in development
# and need to be able to get past the maintenance mode.
# One might call this the 'allow people list'
RewriteCond %{REMOTE_HOST} !^83\.101\.79\.62
RewriteCond %{REMOTE_HOST} !^91\.181\.207\.191
# Make sure the maintenance mode only applies to this domain
# Example: I am hosting different sites on my server
# which could be affected by these rules.
RewriteCond %{HTTP_HOST} ^nocreativity.com$ [OR]
RewriteCond %{HTTP_HOST} ^www.nocreativity.com$
# This is the 'ignore file list'. It allows access to all
# files that are needed to display the maintenance mode page.
# Example: pages, css files, js files, images, anything.
# IMPORTANT: If you don't do this properly, visitors will end up with
# endless redirect loops in their browser.
RewriteCond %{REQUEST_URI} !/offline\.htm$
RewriteCond %{REQUEST_URI} !/css\/style\.css$
RewriteCond %{REQUEST_URI} !/images\/logo\.png$
# Rewrite whatever request is coming in to the maintenance mode page
# The R=302 tells browsers (and search engines) that this
# redirect is only temporarily.
# L stops any other rules below this from executing whenever somebody is redirected.
RewriteRule \.*$ /offline.htm [R=302,L]