Keep in mind some strategies work better than others, depending on what randomly generated level you get.
BSODA And Zesty Bars
This strategy involves collecting bsodas and zesty bars, as they are some of the most useful items in the game. They can help you get away from baldi quickly or shoot him down a long hallway, buying you some time to collect notebooks or escape if you've collected all the notebooks.
Play on Hide-And Seek Mode and get started on Floor 1. As you play through the floor and explore the school, collect as many bsodas and zesty bars as you can. Use quarters to buy bsodas and zesty bars at vending machines if your having trouble finding the items.
I recommend a zesty bar in one slot and bsodas in the other four slots, if you can get that many on one floor. To make collecting the items easier, get all your bsodas and zesty bars before collecting the first notebook. Since Baldi is the slowest at 0 notebooks, it makes it easier to collect the items without baldi catching you, as long as Gotta Sweep doesn't push Baldi into you.
After collecting enough zesty bars and bsodas, get all the notebooks and complete Floor 1. For Floors 2 and 3, repeat these steps although with adjustments depending on what you have and the environment in the level.