The thing about sciatica that sucks is it can be caused by many things. I have spondylolethesis sp and can get bad sc
I find that a few stretches and exercises help a lot. The figure four stretch where you cross the affected leg over the other leg at the knee and gently bring the healthy leg to your chest moving the other leg with it
The other is called a pelvic stabilization. Where you lay on your back and raise your knees so your legs are bent at 90 angle and your feet are still on the ground. Keeping your core and especially the obliques tight, raise one foot two inches and gently set it down, alternate for 60 on each side. Make sure you do not allow your pelvis to move. The purpose of this is to pull your pelvis forward and align it correctly
Generally tight hamstrings will kill you and do will weak lower abs and obliques.
Anti inflamatories are your friend.