Enter your Magento site on the admin side.
Go to the Magento Connect Manager. This option is located in the "System" section, within the "Magento Connect" submenu.
Install a new extension via Magento Connect. It is the first option in the "Install New Extensions" section.
Find and open the Conekta entension for Magento using the search bar.
Click on the "Install Now" button.
Get the extension key by clicking on “Get Extension Key”.
Copy the key that is generated.
Return to Magento Connect Manager (in your Magento Admin) and paste this key in the indicated field.
Click on "Install" and then "Proceed."
After the instalation, be sure to click "Refresh."
After refreshing the installation, return to your Magento Admin. This can be done by clicking on "Return to Admin" at the top of the page.
Go to the Cache Management section. This option is located in the "System" section at the end of the list.
Select and deactivate all the Cache elements by clicking "Disable" and then "Submit".
Perform a flush of the Magento Cache and Cache Storage by clicking each button.
Go to the Configuration section. This option is located in the "System" section at the end of the list.
Search for the option "Payment Methods" and click it.
Configure the four payment methods with your private and public keys. These keys can be found in the "API Keys" section of your Conekta Admin. Remember that it is very important to use the private production key, once you switch to production mode. If you continue to use the sandbox private key, all payments will be fake and you will not receive deposits from Conekta
Within the Conekta Card configuration, you can indicate if you wish to accept Monthly payments without Interest on your site.
Finally, be sure to save the configurations by clicking "Save Config" and you will have successfully finished the installation.