Mainly a daily routine which tries to prevent the infections which cause exacerbations. Those result in a cough, some phlegm, minor breathlessness etc. Then, when you get that double the daily dose of Aktimel (a probiotic taken first thing and an hour before anything else - there are others which also reinforce the immune system), arm exercises to open the chest; wide arm circles, hands from thighs to straight above the head, deep breathing, use reliever and, if you can, a long slow walk.
I am now against antibiotics on the grounds that they are claimed to act against the body's immune system BUT occasionally they are necessary