The first game was really hard. You had to do a very strict time/action management to unlock everything in a single run.
But in this one you can easily end day one with 1k memories, 500+ stamina and more items than you'll ever need.
How to do it:
-buy space compression at the end of tutorial.
-go straight to Akari to unlock Mentai.
-Menko the shit out of everyone you find in your way. every match gives 20xp and takes 7min. Repeated matches give less xp, so if they have a yellow text next to the name you already beaten them once.
-increase stamina every lv up.
-right before the time period ends, go mountain climbing.
-At evening a new set of players will arrive. Menko them all.
-Once you reach 500+ stamina, start increasing max desire at lv up. by then, every mountain climb will give you a lv, so increase stamina just to refill it.
-By then you'll have so much stamina and desire that the only items that matter are protein and erection king. use the rest as presents.
-End of day one. You shouldn't have to worry about stats anymore.
A perfect run at the restaurant gives you 5k, so it should be your main source of cash. Do it at the end of the time period whenever you can. Also because it unlocks the recipes necessary for the Suzuka events.