You can achieve this through the following methods.

Log in to the Care Diary login page and go to Settings > Roles using the left menu.

Once you are on that page, you will find Add button on the top right corner of the page

Click on the Add button and that will open a new page where you can provide the name, description and permissions for this new role.

For any feature, you can choose from four(read, create, update and delete) different types of permission by clicking on the checkbox as shown below.

Once you are happy with the permissions and other information for your new role, click on Create role button which can be found in the bottom right corner of the page.

After creating a role, you can now assign that role to any staff member by going to Staff > Profiles and then clicking on the staff profile you want to assign your new role.

Then click on the Account Settings tab, select your new role from the dropdown in the Roles field and finally hit Save.