After you work on your site, on the spare server or locally, back it up with JoomlaPack.

Not need to install Joomla in the new server until you have developed it, backed it up and are ready to install it on your client's host.

The back up will be your Joomla install.

Install JoomlaPack on the sites(s) you want to move.
Create a back-up of the site.
When you fist start you will see a message:

JoomlaPack may not work as expected
JoomlaPack detected the following potential problems:
• Default output directory in use
• ZIP format selected

For now, it’s safe to ignore.

You'll be moving the back up as soon as it's finished and the zip format works fine.

Run the backup

(This will back up the site and the DB creating an installer package exactly like a Joomla stock install or a Rocket Launcher package with your site's contents)

Navigate to the /administrator/components/com_joomlapack/backupadministrator/components

Here you will find the zipped file you just created.

Download it and after you do so, delete it or move it to another directory.

Upload the zipped installer to your new domain.

Extract it in the root (public_html) or a folder.

Run the installer just like a rocket launcher, the first screen will look a little different.

Of course, you’ll need to set up a DB prior to the install.

You can name as you like it and use any password you like.

During the install, the old DB name, password will be filled in by default, but you can change them if you have created a DB with a new name or password.