I'm lucky as I live in Australia and every summer it clears with the sun and every winter it comes back.
The sun definitely is a major treatment.

I had 48 sessions of UV Light treatment, slowly building up a tolerance to it so I could stay in there for 20 minutes. It did clear up a lot of it and my body was completely covered with thick scales. Unfortunately you can only get the treatment for a certain amount of time because of the dangers of UV. When finished, the psoriasis came back more aggressively and I was so disappointed. I eventually progressed on to Enbrel, which you inject yourself. Very daunting to say the least but it's only once a week and I have to say it's the most effective treatment I've had. I've done 12 weeks (12 injections) and all of the thick scales have gone. My arms and head are completely clear for the first time in 12 years, my legs, back and torso are getting there too. I'm very happy with it. There are a few tests to take before you can start using. Normally just a chest X-ray and blood tests but nothing too bad. It's a success so far so I'm hoping it will continue to clear and get back some sort of life back.
I hope this was of help and good luck with your treatment whatever path you take.

I have just about finished 8 weeks of light treatment 3times a week time going up each session , very effective on all over , who knows if it will come back xx

I'm glad there has been some improvement for you. It hasn't helped me at all really. I've just started using coal tar cream and it's really helping, I've got my fingers crossed xxx

I went for almost 6 months now the demetologist wants to see me in three months,,its not completely clear but I have water retention and can`t go for the treatments now. Im not itch tho,,not now.