In order to accept credit card payments you must link your START account to your own Stripe account. For this you need to setup a new Stripe account or use your existing one and copy the necessary API keys into START.
As long as you do not have set up the Stripe Payment Tokens in START you won't be able get sales over your Online Shop.
1. Create a Stripe Account
If you do not yet have a Stripe account, signup at https://stripe.com. Follow the steps and provide all information required until you have a verified account. If you already have one - just log in.
2. Get and Copy API Tokens from Stripe
When logged into Stripe, browse to the Developers section, select API keys and copy the Publishable key and Secret key (after revealing it).
3. Paste and Save API Tokens in START
Paste the Publishable key and Secret key into START by going to the menu, selecting Profile and browsing to the corresponding section.
4. Supported presentment currencies
See what currencies you can use for making charges and for paying out to your bank account.