Update PR template

Author: RealCLanger

.github/pull_request_template.md

@@ -1,8 +1,15 @@
-Replace this line with a description of this pull request and replace Issue in `fixes #Issue` down below with an issue number. Otherwise PR testing will fail.
+<!-- General instructions for SapMachine PRs:
 
-When integrating please make sure you:
+1. The title of a PR should be "SapMachine (<Release>) #<Issue Number>: <Description>"
+2. A PR needs to refer to an issue in the project by adding the issue number in the last line of the PR body in the form of 'fixes #<Issue Number>
+3. When integrating a PR, please make sure you:
 - Create a merge commit when merging an OpenJDK upstream PR
-- Use Rebase & Merge when your PR contains only one commit with a commit message of the form `SapMachine #<Issue>: <Description>`
-- Use Squash and merge when there are several commits on the PR and with that update the commit message to `SapMachine #<Issue>: <Description>` and remove commit messages from sub-commits
+- Use Rebase & Merge when your PR contains only one commit with a commit message of the form `SapMachine #<Issue Number>: <Description>`
+- Use Squash and Merge when there are several commits on the PR. Update the commit message to `SapMachine #<Issue Number>: <Description>` and remove commit messages from sub-commits
+ -->
 
+<!-- Replace the following line with a description of this pull request -->
+Description
+
+<!-- replace #Issue with the issue number that the PR is referring to. Otherwise PR testing will fail. -->
 fixes #Issue