Pumping at work

I'm EBF and thought this forum would have the best suggestions! I'm returning to work soon, and would love tips as to pumping at work. I'm concerned my supply with drop since I won't be around my LO.  I work 7am-4pm. How often should I pump, every 3hrs? Should I continue to pump after my milk stops? Any tips of transportation or easy ways to clean pumping supplies while there? I've heard you don't need to clean them if they remain in the fridge? That seems unsanitary to me but if it saves time? Right now I pump 1st thing in the morning and at night, but would love guidance and tips you've learned.