You can add or remove field options when adding new field or updating existing field.
To change field option color, click on the desired light position. Then, a color palette will be displayed. Choose your color. Once you are done, click anywhere outside the palette.
Click "Add Field" to add your option.
Note that: The first field option that match its rule will be displayed as the selected option. If a field option doesn't have any rule, it will always match. If all field option doesn't match, field will not be displayed at all. There is currently no way to manually select an option for each issue.
To configure field option rules, click "Rules" on the desired field option. Then, you'll need to select Jira Field, operator and its value. Finally, click "Add" to add the rule. In order for a field option to be selected, all rules will have to match. If one of the rule doesn't match, it will look at the next field option.
Current Supported Rules (more support will be added later):