Tell me how to adjust the flame on my boiler's oil burner (two air adjustments plus fire ring adjustment). Thanks.

this is the one thing that I would always recommend getting done by a pro. however what your looking for is a bright yellowish flame with sharp points. Also using the sound of the flame to help you. Once the boiler is running, loosing the air ring, now you will notice as you turn it the oil holes will either open or close. It's amazing how much air it really doesn't need to burn.

OK, turn the ring and notice the flame by opening the flame site door, (little slide door) if the flame is like a orange / red color then you need to adjust it until you get a consistent yellow bright flame. But you see all this comes with experience.

I don't know the other two air adjustments you mean. There is only that one air ring on most oil burners.