Hopefully I can be of a little help.
Taking a look at the InstandWP website, it appears to be an install version of WordPress that installs into a directory, and then contains all settings etc for the site to run in a local environment.
I am not sure on the file structure of InstantWP, so I would assume that it essentially just creates a version of WordPress to run locally. There should be a wp-content/ folder somewhere within the file structure. This will contain all themes/plugins/media content that is related to your website.
So, there are a few things you are going to need to do, but this is by no means an exhaustive list to get everything working:
- Start by accessing the InstandWP installation and find where your theme is installed. As mentioned earlier it should be located within wp-content/ providing that the install doesn't change where things are stored. You will need to copy out your theme to somewhere else for safekeeping (such as your desktop).
- Then go into the WordPress admin panel, and go to Tools --> Export and export a copy of your Database in CSV format. This will contain any post/page/user/media content you may have created within the site.
- On your live server (where you are hosting your new live installation of WordPress), install a fresh copy of WordPress if you haven't done so already. (If you have skip this step).
- Once this is complete, you should be able to FTP (details of how to do this can be provided by your hosting provider if you don't know how to.) into the live server where WordPress is located and then navigate to the wp-content/ folder located on the server. Once in there enter the theme folder and upload your theme into that directory.
- After all the uploading is complete, you can log into the Admin panel of your live version of WordPress. You are going to need to install the WP-Import plugin in order to import your database back into WordPress. (There are many guides on how to install plugins, which I won't be covering here!)
- Finally activate your new theme in the Admin area, and you should be good to go.
This is only intended as a rough guide of the main steps you need to take in order to get it working, but it should point you in the right direction.
If you get stuck further, feel free to comment on here, and we can try and work out a further solution for you.