Stripe refers to stripe.com
You should buy an SSL certificate from a good certificate provider. We recommend DigiCert — their certificates have very wide acceptance (and in particular should work well on mobile browsers, where many other certificate providers fall short). NameCheap is another good option. They have slightly lower acceptance but their basic certificates cost $10 to $20 a year.
Setup Stripe.
After getting your Stripe account setup. Go to your Account Settings by clicking your account name in the top right of the Stripe Dashboard page.
From your Account setting, select API Keys. You will have a Secret Key and a Publishable Key listed for testing and a Secret Key and a Publishable Key for a live form.
You will need your Secret Key and Publishable Key for your Donate Plus form. Only use your live keys if you are ready to go live with credit card transactions. "If you do not have an SSL certificate installed to your domain, it is not recomended to go live."
Setup Your Add-on
Once you install your Donate Mini add-on.
Add the block to a page and fill in the information it requests.
Give an optional Welcome text above your button. (optional)
Give your form a title. (optional)
Give your form a description. (optional)
Add your API keys from your stripe.com account
Give your button a title. e.g. "Give Now"
Add your currency code. This will show your currency code in the amount field and will set your stripe account up to use and convert to the currency you select.
The button CSS is set to Bootstraps .btn .btn-default but you can even add your own template CSS styles. (optional)
You are set!!!
Do you want more than one on the same page? Just repeat the steps above using custom desciption and price for each one.
Testing
After adding the Donate Plus form to your page, the form will be ready for testing or excepting transactions if your stripe account is live. For test credit card numbers, refer to: https://stripe.com/docs/testing
For a quick success test, simply use the card number 4242 4242 4242 4242 and any valid expiry date and any CVC number.
I am not support for Stripe.com!! but I will support my add-on.