There is no simple way to do this. It would be nice if there was a styles tab somewhere and we could assign styles to any given component and repeat that style but there’s not. You’ll have to set each components color font size margins borders and all of that individually. You can use the all component blocks to do it programmatically but that can take some time to paint things on the screen. It would be nicer if there were just style settings that were very convenient to use.
Come to think about it. Considering the entire system is built on react native, we should in theory be able to access a CSS style sheet. See this link to know more about what I mean.