Add changeset instructions to CONTRIBUTING.md

CONTRIBUTING.md

@@ -72,6 +72,21 @@ If you're contributing to the backend or CLI tooling, be mindful of cross-platfo
 
 Also be sure to skim through our [ADRs](https://github.com/spotify/backstage/tree/master/docs/architecture-decisions) to see if they cover what you're working on. In particular [ADR006: Avoid React.FC and React.SFC](https://github.com/spotify/backstage/blob/master/docs/architecture-decisions/adr006-avoid-react-fc.md) is one to look out for.
 
+# Creating Changesets
+
+We use [changesets](https://github.com/atlassian/changesets) to help us prepare releases. It helps us make sure that every package effected by a change gets a proper version number and an entry in it's CHANGELOG.md. To make the process of generating releases easy it helps when contributors include changesets with their pull requests.
+
+## To create a changeset
+
+1. Run `yarn changeset`
+2. Select which packages you want to include a changeset for
+3. Select impact of change that you're introducing (minor, major or patch)
+4. Add generated changset to Git
+5. Push the commit with your changeset to the branch associated with your PR
+6. Accept our gratitude for making the release process easier on the maintainer
+
+For more information, checkout [adding a changeset](https://github.com/atlassian/changesets/blob/master/docs/adding-a-changeset.md) documentation in changesets repository.
+
 # Code of Conduct
 
 This project adheres to the [Spotify FOSS Code of Conduct][code-of-conduct]. By participating, you are expected to honor this code.