Nothing that takes too much time! Like I don't want to rush back to the table! For example I don't want to start cooking or peeling vegetables and then hear the beeping and run back to the computer!
I keep it simple, bathroom if needed, a walk around the house or up and down the garden, maybe a stretch or two. If I'm hungry I'll pop my pre prepared meal in the microwave, or grab the sandwich from the fridge.... boil the kettle etc.
Then try get to the table with less than a minute to kick off! About 20 seconds is fine to look at the table and look at stacks see where the button is and get in the mind again!
I can then eat while I play and have my tea, grand job!