I remember my first day at the community college in downtown San Antonio.
Put your best foot forward. That is a funny sentence, but it means make sure the first thing you show them is something excellent. This sentence above definitely could be better because it is all "expository" with nothing intriguing.
I remember my first experience in a car with a standard transmission.
A sentence like that introduces an idea, but it lacks action.
I acted like a politician on my first day at the community college in downtown San Antonio.
This sentence has some action, but it could still be even better if I have a real, visible action verb:
I acted like a politician on my first day at the community college in downtown San Antonio, trying to make a good impression on everyone.
Then, it can become intriguing if you squeeze even more of your meaning in there with a hint about something:
I learned that it is not a good idea to act like a politician on one's first day at the community college in downtown San Antonio.---a sentence like this leaves the reader feeling curious.
So... try to do something intriguing with that first sentence to HOOK the reader's attention.