wget https://modx.com/download/direct?id=modx-2.6.5-pl.zip

unzip modx-2*
cd modx-2*
cp -R * /var/www/xxxx
cp ht.access /var/www/xxxx/.htaccess
cd /var/www/xxxx
mkdir assets
mkdir assets/components
mkdir assets/files
mkdir core/components
touch core/config/config.inc.php
chgrp -R www-data *
chown -R www-data *
chmod -R 750 *
chmod -R 770 core/packages
chmod -R 770 core/cache
chmod -R 770 core/export
chmod -R 770 core/components
chmod 770 core/config/config.inc.php
chmod -R 770 manager
chmod -R 770 assets
chmod -R 770 connectors
cd ..
chgrp -R www-data xxxx
chmod 770 xxxx

http://xxxx.com/setup

cd /var/www/xxxx
rm -r setup

cd core/config
chmod 440 config.inc.php