You need to put all your files into a folder named whatever your theme is called and add it to the /theme folder. Caution not the concrete/theme folder.
You will need a 120x90 image named thumbnail.png and a .txt file called description.txt with your theme name and brief description in it.
You will also need at least one of your theme files to be called default.php
You will then need to go to your site and activate the theme which can be done via the Dashboard - Theme section in your C5 install.

Happy site building :)

Thanks for some light, but still confused. The mud is now only neck high.

I started my devel originally using a prepaid theme from the C5 website, jb_night_city.

also have 3 add-on software i use on my website will need to move
these 4 files and their content. They are located in my packages directory on my home computer C5 directory.

I created the thumbnail.png and the description.txt

now what??

now about the default.php file, there is already a default.php file inside the above jb_night+city theme ,

now do i use this php file or create a new one and then what is the content for the new create php file. Do i copy anything from the old default.php or just create a new php file?? please advise.

what files will I then copy from my home computer C5 directory into my server httpdocs/theme directory. (is this correct????)

please provide further direction
thx
blackadder