To add a task to a matter, open the matter.
Select the milestone that you want to add the task to.
Scroll to the bottom of the 'To Do' column and click on the '+ Create task' tile.
Fill in the details:
Task name (mandatory)
Task description (optional)
Due date (will default to the target date of the current milestone, but can be changed to an earlier date)
Click on 'create'.
Note that if you want to make task due date later than the target date of the milestone you will first have to edit the milestone dates. This is avoid setting tasks later than the relevant deadline they are associated with.
You have all the formatting options when writing the task description (except for tagging other users - use the task notes feature for this), such as:
Headings
Bold
Italics
Links
Checklists
Bullet points