Integrate SM with external application using RESTFUL API

Hi Experts,

SM 9.52.

I need your help please.

I know how to integrate our SM with external application using SOAP (wsdl files).

1- Run WSDL to JS to convert the exposed wsdl (of the external application)
2- Create a customized javascript to Add/Update the tickets in the external application
3- Call the script from SM Workflow Process Designer

Now we are doing another integration with a different customer/application which supports only REST api.

What are the steps that need to be done? Are they similar to the above?
Should I run WSDL to JS for REST URL? or this is just for SOAP? 
Does anyone have a sample script from SM that connects to a API Application?

I have read all web services document but it does not help a lot.

Please help.