Open Netscaler and generate RSA Key

Create a new RSA key 

Create a new CSR

Request File Name is name.csr

Key FileName is the RSA key you just generated

Digest Method : SHA 256

Use PEM and Enter Company Details

Once CSR Created , download and open this key and enter it into your Cert Provider.

Download the New Key as a .PEM format 

Upload the New Key to the Certificates

Install the Certificate

Certificate File Name is the one you have uploaded from your provider ( .pem ) 

The Key File Name is the RSA Key you generated at the start

Install CA/Intermediate certs

If the certificate requires any Intermediate certs, Upload these to Certificates, then install

Link the CA Certificates with the new SSL Certificate

Right Click on your certificate you have installed under following directory and click Link , choose the CA cert that matches its chain

Change the SSL Cert on the Netscaler Virtual Server and Load Balancer

Navigate to your Virtual Server

Choose Server Certificate 

Add Binding

Select your new certificate . Select and Bind

Repeat step on Load Balancer

Make sure you SAVE THE CONFIG!

Test the chain using : https://whatsmychaincert.com/