Choose Insert, and then More Gadgets.
In the Google Sites Editor, open the Insert menu. You should be able to see a list of available gadgets you can install on your site, including Tables, Links, and Images Click on the More Gadgets option. This will let you add editable tools like POWr Image Slider to your site.
Paste in URL
You will see the Gadget manager. Click on Add Gadget by URL. Copy and paste this URL into the box. Click on Add to finish.
Change Height and Width
Now that you have embedded your new, fully customizable Image Slider Widget onto your website, you'll probably want to change the shape and size of the Widget. Using the options in the pop-up window, choose the height and width of your plugin. If you'd like, you can add a border, title or scrollbar to your Image Slider Widget, but we don't advise it. There is more editing control through the plugin itself.
Set up POWr Image Slider
Go to the live Google Sites website and click the gear icon in the top right corner of the Image Slider Widget.
In the POWr Editor, click Import Existing Image Slider, find Image Slider- and click Copy.