Interswitch Webpay WooCommerce Payment Gateway

Login to your WordPress Admin area
Go to "Plugins > Add New" from the left hand menu
In the search box type "Interswitch Webpay WooCommerce Payment Gateway"
From the search result you will see "Interswitch Webpay WooCommerce Payment Gateway" click on "Install Now" to install the plugin
A popup window will ask you to confirm your wish to install the Plugin.

Note:

If this is the first time you've installed a WordPress Plugin, you may need to enter the FTP login credential information. If you've installed a Plugin before, it will still have the login information. This information is available through your web server host.

Click "Proceed" to continue the installation. The resulting installation screen will list the installation as successful or note any problems during the install.
If successful, click "Activate Plugin" to activate it.
Open the settings page for WooCommerce and click the "Payment Gateways," tab.
Click on the sub tab for "Interswitch Webpay".
Configure your "Interswitch Webpay" settings. See below for details.

Manual Installation

Download the plugin zip file
Login to your WordPress Admin. Click on "Plugins > Add New" from the left hand menu.
Click on the "Upload" option, then click "Choose File" to select the zip file from your computer. Once selected, press "OK" and press the "Install Now" button.
Activate the plugin.
Open the settings page for WooCommerce and click the "Payment Gateways," tab.
Click on the sub tab for "Interswitch Webpay".
Configure your "Interswitch Webpay" settings. See below for details.

Configure the plugin

To configure the plugin, go to WooCommerce > Settings from the left hand menu, then click "Payment Gateways" from the top tab. You should see "Interswitch Webpay" as an option at the top of the screen. Click on it to configure the payment gateway.

You can select the radio button next to the Interswitch Webpay from the list of payment gateways available to make it the default gateway.

Enable/Disable - check the box to enable Interswitch Webpay Payment Gateway.
Title - allows you to determine what your customers will see this payment option as on the checkout page.
Description - controls the message that appears under the payment fields on the checkout page. Here you can list the types of cards you accept.
Product ID - enter your Product Identifier for PAYDirect here. This will be given to you by Interswitch.
Pay Item ID - enter your PAYDirect Payment Item ID here. This will be given to you by Interswitch.
Mac Key - enter your Mac Key here. This will be given to you by Interswitch
Test Mode - Tick this to enable test mode, remember to untick this if you are ready to accepting live payment on your site.
Click on Save Changes for the changes you made to be effected.

You need to have WooCommerce plugin installed and activated on your WordPress site.
You need to signup for Interswitch Webpay on Interswitch