Changing a user's permission set
In brief
User permission sets are easily updated from the Users page. This allows you to quickly manage a user's access control within a project.
Required permissions
Can update users and their permissions
Firstly, you will need to navigate to the Users page of your chosen project. Once there, either search for the desired user or just navigate through the table and right click their username. A small dropdown will appear with one of the options being 'Change permissions'
This will bring up the permissions window for the user. From there, you have a number of options depending on what you're looking to achieve. You can select an existing permission set by clicking the 'Existing permission set' search box and choosing from the options available. Alternatively, click the '+' symbol to create a new permission set right there and then. Remember any newly add permission set permissions will be added to that user, they wont replace the existing (unless you remove them first). If you want to remove any existing permission sets just click the little 'x' next to the set you wish to remove.
The 'Explicit permissions' tab is where you can add or remove permissions which will apply to that user only. Updating permissions here will override any permission set permissions, so it saves you having to recreate a new permission set just to make a small change. Generally speaking though, it's much safer to just make a new permission set!