Stand in the shoulder of giants....."
Check what big companies are doing. What is like to buy at Amazon.com?
Browse all, add things to your cart, delete, update and finally when you are ready to checkout they ask you a simple thing:
Enter your email address : [_________]
() I am a new customer.
(You'll create a password later)
() I am a returning customer,
and my password is:
[__________]
If the buyer is an existing customer, validate the password load the personal info and go to next step.
If customer is new, use the email address as the username and ask for the person's info, at the same time just ask for a password. All done in one screen. The user is registering to your site and completing the transaction (read: giving you money...) at the same time without being bothered multiple times.
Imagine asking a new customer for the login info at the start of the shopping experience.. User looses that momentum and shopping impulse and rathers go somewhere else or just decides not to buy the product at all, not from you, not from anywhere.
You have seconds to get the users attention, throw the sales pitch about the product and then receive the payment. Why would you throw an extra step of difficulty ?
grtfercho çB^]\..
"Imagination is more important than Knowledge" A. Einstein
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