Started as a shower thought (literally in the shower), but decided to make it more open-ended.
My answer to this would be “watch future seasons of anime that I am waiting on”.
I don’t see how that could cause a huge ripple through time.
Parade for the astronauts coming back from the moon?
What’s another guy standing around, just minding my own business.
OR THE OPENING OF A BRIDGE IN BRITISH COLUMBIA IN 1941?! What are you, some sort of time-travelling bridge freak?