Using this extension you can present a Size Chart for your products, which can help your customer to check exactly which size they have. Especially this extension is made for configurable products and more useful to Online Garment Stores.
Goto Admin -> Add-ons -> Manage add-ons
Click on ADD(+) Button.
Upload the downloaded addon zip file.
Click on Upload & install button.
Now you can see Size Chart tab on main menu in admin.
Click on Size Chart -> Add New Template to create a temlate.
Click on Manage Templates to manage the templates.