How to make a paper airplane

Get your A4 piece of paper flat on a table of some sort

Fold your piece of paper in half as precisely as possible

Fold the two top corners inside

Fold the top part downwards

Then fold these two top corners in like that

Fold the small triangle on top of the two corners to hold them down

Fold it in half again

Fold the edges inside to line with the bottom parts

Add tape on the top so air doesn't go through and slow it down

You can then design it as you like

There you go, you've got your own paper airplane!