Much of this answer is going to be dependent on which particular character you have. I think that one way this can be seen is through Miller's analysis of Salem, itself. Miller describes Salem as a community that approached consciousness rooted with a binary opposition within it:
For these reasons, among others, they carried about an air of innate resistance, even of persecution. Their fathers had, of course, been persecuted in England... They believed, in short, that they held in their steady hands the candle that would light the world. We have inherited this belief, and it has helped and hurt us. It helped them with the discipline it gave them. They were a dedicated folk, by and large, and they gave to be to survive the life they had chosen or been born into this country.
Miler makes the argument that part of the reason why the hysteria took such a hold in Salem was because of the way it viewed life in binary terms. Either something was right and holy or it was wrong and evil. There was no complexity in consciousness for those who lived in Salem. There were no nuanced approaches to being in the world. Life was clearly divided and when individuals were on the "wrong" side, they were persecuted.
It is in this light where you can examine how specific characters either fuel or calm the hysteria of Salem. Characters were fundamentally divided or manipulated into being on one side or another. Some fueled the hysteria for their own benefit. Abigail Williams fanned the flames of hysteria in order to consolidate her own power, and in her coveting of Proctor. Hathorne, Danforth, and Parris acted in a similar way so that their own power could be increased. Mr. Putnam acts in a manner that fuels the hysteria so he can gain control over land acquisition in Salem, while his wife fuels the hysteria so that she can gain some level of closure over the death of her infant children. Characters like Hale wanted to calm the hysteria, but they became easily manipulated as part of those who fueled the hysteria. On the other side were the individuals who sought to calm the hysteria, such as Goody Nurse, Giles Corey, and John Proctor. Those who sought to calm the hysteria might not have accomplished their goal, but because they stood diametrically opposed to those who actively benefitted from the hysteria, they can be seen as opposites. It is in this light where Miller's development of Salem as a community that suffered greatly as a result of the binary mode of understanding in the world can make it relatively easy to see which characters either fuel or calm the hysteria.
My particular character is John Proctor.