need A funnel in a hurry?

Sooner or later you will find yourself saying something  like "this would be so much easier/faster, if I only had a funnel."  Well here ya go, the quickest, easiest and probably cheapest way to make a funnel for liquids. It's so easy, you could be done by now.

Step 1: Materials

You will need.
 A plastic bottle I like 2 liters because they are wide bottles with narrow necks.   but any old bottle will work.
A knife,  razor blade is probably best but if it's sharp it'll work