RewriteEngine On RewriteBase / RewriteRule ^ - [F] ErrorDocument 403 "Your message here."
or
RewriteEngine On RewriteBase / RewriteRule ^ - [F] ErrorDocument 403 "<div style='font-family:Arial,Helvetica,sans-serif;text-align:center;margin-top:12%;'><h2 style='font-size:28px;font-weight:normal;color:#333;margin-bottom:12px;'>What ever you want to say</h2></div>"
or recursively:
Order Allow,Deny Deny from all ErrorDocument 403 "Your message here"
Require ip 100.30.128.4 117.40.128.5 ErrorDocument 403 "Access from..."