Simply done. Click on Profile at the top. Go to Look & Feel, if it says Forum Default this means its GMT or Greenwich Mean Time. Two lines down it says "Time Offset" then put in how many hours you are away from Greenwich, England. A helpful place to find out how many negative (or positive) numbers you need to put is at
this Wikipedia article. That should work. If you see a star next to the region, it means you need to add an hour for Daylight Savings Time.
For me, left coast during standard time is -9. During daylight savings its -8.
If you want to set your board time to Parallel time, I would have no idea how to figure it out or if it is even capable of calculation such time.