How to create an Action using C#

Hello,

I need to make an action that will create an Opportunity using C#. This action should be executed using JavaScript( i will use Process.js). 

I have some difficulties to understand which steps do i need to do create an action in C#. I have found some online guides about that, but I can't understand the best.

Can someone give me some short guidelines how to do it.

I am not asking you to write a code, just some tips like:

-create new project in Visual Studio

   - make new class and write your code

-make signing key

-add next references: ....

-regster it as a...

- go to CRM  and activate it

...

or whatever I need to do. Also if there is some article, tutorial you think is good, I would appreciate you to send me a link.

Thanks!