URL Redirect for 'Submit' button

I am using a code injection to redirect to a different URL when customers click "Add to Cart". However, I want to adjust it to redirect after the customer fills out my product form instead. The code snippet I'm using is '.sqs-add-to-cart-button'.

Any ideas on how to do this?

+ 1 for this.  Custom cakes have too many options to cover with variations, so am looking to chain several products into the same order - eg: Base type -> Icing Icing variations->decorations. But I still need the product form to capture stuff like piped messages, filling flavors etc.

Just out of interest what code snippet do you use to do the redirect. I'm desperately trying to redirect the add to cart button to an external URL as we can't run payments through our squarespace site. Any help would be appreciated. Thanks