1. Set the debug to false in .env
2. Set the APP_ENV to production in .env
3. [NA] /public should be there in APP_URL in .env
4. Remove .git directory from original zip and then make a package. (Confirmed with vendor)
5. [NA] Select Email Settings Driver as "SMTP" in manual installation.
6. [NA] Fill following details in SMTP settings.

From Address = Email address
Username = Email address
Encryption = SSL/TLS
Host = smtp.gmail.com
Port = 465

7. Add the following line to the .htaccess file in the root folder :
<IfModule mod_alias.c>
RedirectMatch 301 ^[[relativeurl]]/$ [[softurl]]/public/index.php
</IfModule>
8. PHP REQUIREMENT LINK : https://invoiceninja.github.io/docs/self-host/self-host-installation#server-requirements
9. Release date : https://github.com/invoiceninja/invoiceninja/releases
10. We exclude logo image path while upgrade i.e public/images/invoiceninja-logo.png since user's custom logo was getting overwritten post upgrade. (Check when we add upgrade)
11. Explicitly add DISABLE_AUTO_UPDATE=true in .env and keep the value true i.e 'disable_auto_update' => true in bootstrap/cache/config.php.
(Confirmed with vendor via email)
12. Keep UPDATE_SECRET value in all installation through Softaculous as it is required for upgrade.
13. Since 5.3.31 .env.example has to be renamed to .env while manual installation, as mentioned here in the documentation link : 
https://invoiceninja.github.io/en/self-host-installation/#final-setup-steps and our conversation with vendor over email
14. Script gets installed in a sub-directory, however some of the functionality does not work. eg. Logo is not visible in invoice. Still we can make manual installation and test the script in a sub directory. (Since 5.9.4 version script only works in a root dir)
15. Download 'invoiceninja.tar' package from github.
16. We have set the cron for every minute referring to following guide and on users request on ticket.
https://invoiceninja.github.io/en/self-host/#add-the-cron-job
17. In .env file Change MAIL_MAILER="smtp" to MAIL_MAILER="log" suggested by vendor for the login issue with different network