There are fanfictions where Naruto sets up a fake mission for Team 7. He creates a whole scenario where they think they are going to rescue a princess but in reality, it's just a big joke. He has also been depicted as changing the signs on the training grounds so that when Team 7 shows up for training, they end up in the wrong place completely.
Well, in some fanfictions, Naruto has been known to put salt instead of sugar in Sakura's tea. She takes a big sip and spits it out right away, which is quite funny. Also, he might play a prank where he makes it seem like Sasuke has a crush on Sakura by leaving fake love letters from Sasuke around. It causes all kinds of chaos and blushing between the two of them.
Sakura's reactions can vary. Sometimes she tries to get revenge on Naruto for his pranks. If he plays a prank that makes her look silly in front of Sasuke, like the fake love letter prank, she'll be really mad and try to think of a way to make Naruto pay. Sasuke might pretend not to care, but if the prank affects his image too much, like the hair product switch, he'll give Naruto a cold stare. Kakashi is more laid - back and just watches the whole thing unfold like it's entertainment.
One of the funniest pranks could be that the Kyuubi makes Naruto's clones start singing cheesy pop songs instead of following his commands. Naruto often uses his clones in battles and for various tasks. So when he sends them to attack an enemy, they all start singing and dancing instead. This would not only be a shock to Naruto but also to his opponents. Another great prank would be the Kyuubi making Naruto's body move in the opposite direction of what he wants. So when he tries to jump forward, he jumps backward instead, leading to all sorts of comical situations.
In some Naruto prank call fanfictions, one hilarious prank could be Naruto calling Sasuke and pretending to be a long - lost relative. He might use a really goofy voice and say things like 'Sasuke, it's your second - cousin twice removed, and I've got a really important message for you!'. Another could be Shikamaru prank - calling Ino and trying to convince her that there's a new beauty product that will make her hair fall out if she uses it. Just to see her over - the - top reaction.
One of the pranks Naruto might do is to mess with the Anbu's communication system. He could use his knowledge of chakra and some basic electronics (if we assume some modern - like elements in the fanfiction) to scramble their signals. This would make it difficult for them to coordinate with each other, and they'd be running around trying to figure out what's wrong while Naruto watches from a hiding place, having a great laugh.
Naruto could enlist the help of his friends like Shikamaru. Shikamaru could come up with a really elaborate plan. For example, they could set up a fake mission where Ibiki thinks he's in charge, but it's all just a setup for a series of pranks. They could have actors pretending to be enemy ninjas who act really silly instead of being threatening. And Naruto could keep popping up in unexpected places during this 'mission' to further annoy Ibiki.
In a Naruto pranks Hyuuga fanfiction, Naruto might use his typical mischievous tactics. For example, he could use his shadow clone jutsu to create chaos around the Hyuuga compound. Maybe he'd make clones that pretend to be important visitors and then act all silly to embarrass the Hyuuga. It would be a really funny scenario as the serious Hyuuga clan tries to deal with Naruto's antics.
One common prank could be Naruto switching the Hyuga clan's training dummies' positions. This would mess up their training routine as the Hyuga are very precise in their movements and training. They rely on the familiar layout of the training area, and Naruto's prank would throw them off balance.
In some Naruto fanfiction, Kurama might prank Naruto by making his chakra go haywire at inconvenient times, like during a spar with Sasuke. It could be a harmless prank where Naruto's Rasengan suddenly fizzles out because Kurama messed with the chakra flow just for fun.
Maybe Naruto uses his shadow clone jutsu to create a bunch of clones that keep following Tsunade around, asking her silly questions all day long. This would drive her crazy as she tries to get her work done. For example, they could keep asking her about her love life or her opinions on the latest ninja gadgets.
Peter could play a really funny prank on the Avengers. He might use his agility to secretly attach some helium balloons to Captain America's shield. So when Cap tries to throw it, it goes all wobbly in the air because of the balloons. And for the Hulk, Peter could create a holographic image of a really cute kitten right in front of him. Since the Hulk is usually associated with destruction and anger, seeing a cute kitten would be a really unexpected and humorous situation.