Guys listen. Guys? Okay. Listen.
Pre-register for your races.
Almost all road races offer both pre-registration, and raceday registration. Do the first one.
Because if you don’t, you might forget to tell your race buddy and then she’ll be mad at you. And you might end up cutting it a tad close to the start time. And you might possibly have forgotten to bring enough cash for registration and need to scramble around to find it before the race starts.
All this can be solved by registering for your race ahead of time.
Definitely none of this has been informed by personal experience.