how do you upgrade a leveled weapon?

[sircrunch]

I have a bow i'm leveling.

According to the wiki

"Upon gaining a level crafted weapons will gain 3 points which you can spend on upgrades. Non-crafted weapons will yield 5 points per level."

How do you upgrade it?
It doesn't say how in the wiki

I've so far leveled my bow up to 11 and haven't upgraded it any.

[Nelapsi]

Single click the weapon and select Information from the menu, that is the user interface to spend the points.