Before you can start playing around with your new theme, let’s first check what the theme package includes. After you have downloaded the light.zip file from Themeforest and unzipped it, it should reveal the following folders:
Upload the Theme
You have two options how to upload themes in WordPress and I will cover them both now. You can either upload all theme files via FTP or you can use WordPress Theme Uploader. It really doesn’t matter at all which one of these techniques you want to use, so choose the one which seems to make more sense to you.
So I assume you do know how to use your FTP client of choice (like Filezilla), but if you don’t, then try Theme Uploader technique.
First login o your FTP account and navigate to your WordPress installation directory and in there go to wp-content\themes folder.
Now put FTP client to the side for a while and head back to Light Theme folder, which you just unzipped light.zip.
There should be only one folder, called Light. To make sure you are in the right place, check that folder contains files like index.php, functions.php and style.css.
If everything looks good you are ready to upload this light folder to wp-content\themes, which you found earlier.
Navigate to Appearance -> Themes -> Add New -> Upload Theme. Select light.zip file. Press the Install Now button to upload and install the theme.
Activate the Theme
After the theme is successfully uploaded, head on to Appearance -> Themes, in WordPress backend. There should be now one new theme called. Find it and just click Activate (if the theme was uploaded via FTP).
Or click Activate right after theme was installed (if it was installed with Theme Uploader)