You can choose to show either the sign visualiser or a custom design form as the initial screen that shows when your customers visit your site. This feature allows you to have multiple links on your site such as "Upload your own design" and "Personalise my sign" which link to the respective custom design form and default visualiser.
How to enable in Shopify
Login to your Shopify admin
Select "Sales channels" -> "Online store" from the left-side menu
Click "customize" on your active theme
Select your customiser product template from the dropdown at the top of the screen
Select your Sign Customiser app block
Select "Custom Design" from the "Initial Screen" dropdown
How to enable in our Universal app
To enable this feature, update your iframe URL to include the initial_screen=CUSTOM_DESIGN query parameter.
For example, if this is your customiser URL:
<iframe src="https://web.signcustomiser.com/embed/XXX"></iframe>
You should update it to this:
<iframe src="https://web.signcustomiser.com/embed/XXX?initial_screen=CUSTOM_DESIGN"></iframe>