It's been said a million times.

1- You need to make a base of your joke.

Ex:
Q: Why did the Chocobo cross the road.
A: Because it is the transportation
or
A: Because you are riding it.

2- You change it up with Faqs.

Q: Why did the Chocobo cross the river.
A: Because it Can, that's why.

3- And then make it Original.

Q: Why did the Chocobo cross the Road?
Squall: I don't know, why?
Chocobo hits Squall hard from the side
*Bang!*
Mother Chocobo: To get Even! That's why!

4- You can even add more detail.

Q: Why did the Chocobo cross the Road?
Squall: I don't know, why?
Chocobo hits Squall hard from the side
*Bang!*
Mother Chocobo: To get Even! That's why!
...
Baby Chocobo:
Squall:


How's that!?
Simple joke made better.