I have spinal stenosis as well and have had a horrid bout of sciatica as a result. The only thing that relieved it ultimately was an epidural injection.
The specific things that aggravate the condition are: lifting anything heavier than a half gallon of milk; bending backwards, sitting for more than 45 minutes at a time, twisting the spine.
Before I get out of bed in the morning I do a series of stretches including knees to chest and holding for several seconds; repeat a few times with each leg - then, both legs together.
I hope you get relief soon.