Dear member
Your Question is still not complete, It depends on what kind of Visa you are applying for him.
Also, your Legal representative of the firm should let you know the process and all you have to do is coordinate with the person to get all the documents. (considering Mgmt has asked you to coordinate)
Every firm has a legal representatuve who will help you file Visa for the employees in the company.
Sincee you have asked the process, you can first ask what kind of visa he or she needs and then search it on net. you should get all the informastion on US and UK government websites.
To help you. below is the link which explains the process for US.
Hope this helps!!
US Visa, Visitor Visa, Immigration