Improves CONTRIBUTING guide

CONTRIBUTING.md

@@ -20,7 +20,10 @@ It is also recommended to take a look at these resources:
 
 ## First steps
 
-1.
+1. Fork [our repo](https://github.com/wemake-services/wemake-python-styleguide), here's the [guide on forking](https://help.github.com/en/github/getting-started-with-github/fork-a-repo)
+2. [Clone your new repo](https://help.github.com/en/github/creating-cloning-and-archiving-repositories/cloning-a-repository) (forked repo) to have a local copy of the code
+3. Apply the required changes! See developer docs on how to work with the code
+4. Send a Pull Request to our original repo. Here's [the helpful guide](https://opensource.com/article/19/7/create-pull-request-github) on how to do that
 
 
 ## Developer's documentation