It depends on if your car is a little bit off, or a lot off, if it is a lot, and there are others with the same car, ask if you can see what setup they are running, chances are there maybe a few key differences. (for example, going from a high grip track to a low grip track could net completely different roll center and camberlink options) Start with that. If the car is "working" just off pace, then it is better to take the one change at a time approach as to not risk making the car undrivable.