1) Enter all the keys and copy the cms-data folder to the server. The API-key you can get from Snipcart if you have registered an account. Make sure to enter your web address in the RW Settings General and Publishing. Don't use www but rather https://yourdomain.com
2) After doing all that you will have to register the READ and POST page by following the actions on the screen. Copy the .htaccess code, then go to Publishing and enter them directly into the dialog box and save.
3) Now you are good to go. Enjoy!!