Focus then on your destination rather than the item you don't want to spill. It works!
One of my homeboys who used to be a waiter told me this same thing. He said don't watch the drink just focus on where you going.

It really does work. I think if you look at the drink you try to correct for the liquid moving and you end up making it even more unstable and eventually it spills. Or something like that.
 
  • Like
Reactions: B_A