What you need:
2 slices of bread
Peanut butter – any kind
Jelly/Jam – high quality if possible. The more fruit the better!
There are two very important things to keep in mind when making a peanut butter and jelly sandwich (aka PBJ). First, this sandwich is much much better FRESH!! If it is left too long, the jam eventually sinks into the bread, and changes the flavor of the sandwich completely! The other important point is to go HEAVY on the peanut butter and the jam. Lots of both makes a delicious sandwich!!
Directions:
Spread a good amount of peanut butter on one side of both pieces of bread. This is important to prevent the jam from soaking into the bread! Next, spread a large amount of jam on one of the slices. Add the other slice, and voila!! Sounds easy? That´s because it is! But it is also delicious 
**Some people like to add butter on both sides of the bread. I´m not a fan, as I find I don´t like the flavor of the butter. Of course, it is worth testing to see if you like it.
As for the type of bread, jam, peanut butter, that is all up to personal preference. My favorite is: a creamy Kraft peanut butter, a jam with lots and lots of fruit (homemade if possible) and whole grain bread.
Variations:
Instead of jam, use nutella, to make a Peanut Butter Nutella Sandwich!
Here is a fun video, demonstrating how one may feel when about to eat this classic sandwich: