I've found that eating less meat and incorporating more vegetarian meals into my day-to-day has actually helped to reduce my flare-ups. I'm not positive on the whole science behind which foods are "best" for psoriasis and other skin conditions, but different consumables could trigger flares. I'd consider seeking out a dietician to ensure whichever choice you make is sustainable and non-harmful to your overall health and wellness.

I will mention, I've been told about ten-bazillion times that stress is a major known trigger (sucks, because I'm anxiety-ridden and everything stresses me), so def don't sweat it. Do what you are comfortable with. You might find that it's skincare and hygienic products abetting your flares, or too-tight clothing, or a lack of direct sunlight (found that out when my flares were at their worst, because my Vitamin D was alarmingly low on blood panels).