You can create a default post template for each category in your workspace. These post templates act as predefined texts that are inserted into the description part upon selection of a category. They help the user to define a structure for the posts of a certain category (feature request, issue, bug report).
Create a post template
Go to "Settings" > "Categories"
Select "Templates" at the bottom of your post list
Select a category and add some predefined text
If you are ready, press "Save"
Below, you find an example of what a post template for a "bug report" might look like.
### Expected Behavior
<!--- Tell us what should happen -->
### Current Behavior
<!--- Tell us what happens instead of the expected behavior -->
### Possible Solution
<!--- Not obligatory, but suggest a fix/reason for the bug, -->
### Steps to Reproduce
<!--- Provide a link to a live example, or an unambiguous set of steps to -->
<!--- reproduce this bug. Include code to reproduce, if relevant -->
### Context (Environment)
<!--- How has this issue affected you? What are you trying to accomplish? -->
<!--- Providing context helps us come up with a solution that is most useful in the real world -->