April Fools' Day is the first day of April every single year, which makes it easy to remember (you know, for planning purposes). Each year on this day, people play pranks on their friends, family members, coworkers, and sometimes strangers. If you're pranking everyone in sight, then you'll probably want easy April Fools' Day pranks to play that are relatively low-effort, but still in the spirit of the holiday.
In my opinion, April Fools' Day pranks should be lighthearted and fun—never mean. You should be able to laugh them off pretty easily. Anything too serious or that causes too much worry, fear, or misery should ideally be avoided. Before deciding on a practical joke, think through your audience and whether they'll react well or not.
Potential prank ideas can range from telling someone something funny to playfully messing with their food, clothing, or routines. Say, for instance, you don't have any set plans with a friend that day. Texting them and asking when they'll arrive, saying you're on your way, or telling them that you're running late, but you'll meet them there will usually ultimately be harmless, but might elicit a few giggles once you've let them in on the joke. Just remember, the day is supposed to be fun and silly, and your pranks will (hopefully) be appreciated.