Things You'll Need
Clean strap wrench
Hack saw or pipe
"Bottle trap" is a term that is often used to describe a part of the drainage system of your sink. People in the plumbing industry often use this term to describe the thin and straight waste pipes that have no curves or have a U- or S-bend to it. A second pipe is usually branched from the first one, right above its halfway point. You can easily install a bottle trap to your sink without the help of a plumber or a professional--you need a few household tools.
Turn off the water supply, then install the pop-up drain to your lavatory according to its manufacturer's instructions.
Remove your inlet nut, or the largest nut attached near your lavatory, from the body of your bottle trap. Make sure the seal is inside your inlet nut.
Place the body of your bottle trap around your tailpiece, then tighten the inlet nut with your clean strap wrench until it is flush against your bottle trap body.
Measure the length from your drain stub-out to your outlet nut's innermost edge. The outlet nut is the largest nut near the pipe. Cut the pipe with your hacksaw if the length measures less than 12 inches. Purchase a pipe with an appropriate length should the length be more than 12 inches.
Remove your outlet nut from the body of your bottle trap, while making sure that the seal and ring are inside your outlet nut.
Ensure a proper compression fit by inserting at least 1 inch of the pipe inside your outlet nut. Slide your outlet nut with its ring and seal onto your pipe, with your threads facing towards the body of the bottle trap.
Insert your pipe into the bottle trap body's side. Tighten your outlet nut with your wrench until it is flush against the body of your bottle trap.
Slide the flange onto your pipe's free end. Insert your pipe into the drain stub-out that has the seal, then push your flange right against the wall.
Turn on your main water supply. Let the water run through the drain and check if there are leaks.