My son, who is now 13 months old, was diagnosed at 3 months. After much trial and error we found some triggers and solutions to flare ups.
He is breast fed and so we played with my wife's diet to determine any trigger foods. Cow's milk protein was noted by both of us so took action there. She doesn't go crazy with milk now. Eg; at breakfast she won't have cheese in her omelet if she is having coffee with cream, a cheesey dinner means no dairy in her desert ect. We determined recently that he is in fact allergic to cow's milk protein.
As far as the boy's skin goes we have multiple weapons in our arsenal and we have successfully avoided steroidal creams and immuno-suppressing ointments both of which should NOT be used on children under two despite what your doctor says.
The two major products we utilized were "Aquaphor Healing Ointment" and "Aveeno Baby Fragrance Free Daily Moisture Lotion" and both were successful. We opted to use the Aveeno product as our primary one because we saw slightly better results and felt the colloidal oatmeal and dimethicone were safer than petrolatum for long term use. We cream him up at each diaper change. We also found that a daily bath without soap and then a quick cream up immediately after drying him worked wonders - we call it the "Dunk and Gunk". We use "Aveeno Baby Soothing Relief Creamy Wash" twice a week as a bath soap, it slightly outperformed Cetaphil in our opinion(Cetaphil is good though). Olive oil on his scalp keeps the skin nice and moist as well.
For flare ups our main worry is him scratching and drawing blood. We step up our efforts at that point and bring in some new weapons. Since the flare ups are usually allergic in nature we will sometimes use baby benedryl to calm them down. We also use "Calendula" lotion on him. Calendula is good at preventing infections from starting thru broken skin. On areas he is scratching alot we sometimes used "Florasone" which is an anti-itch cream. My wife is a little uncomfortable with it as there were few studies on it so we use it sparingly.
We don't put anything polyester on him. We wash his clothes and sheets in a mild baby detergent and use the second rinse cycle on the washer - that is very important! Even a good washer only gets 95% of the soap out on the first rinse.
Thats is all I can think of now. Your child's skin is different than our child's so different things may work better. The most important thing is to research everything, be vigilant and patient. Best of luck to you!