Okay, now for the fun part: choosing your commander
For example, I could see using it to find a strategy-specific equipment such as Colossus Hammer or Umezawa's Jitte
However, you can use them to fuel the abilities of your permanents on the board, so they can be a powerful source of mana
Being honest about a decks power is paramount, and a common, respected practice is to bring multiple decks of varying power levels to an LGS
So, if some triggers go off between the resolution of Sundial of the Infinites ability and the beginning of the cleanup step, including those that trigger at the beginning of cleanup step, they all go onto the stack, the active player gets priority and then the usual chores