How to fix a bath sink stopper with This Old House

Watch this video from This Old House to learn how to fix a bath sink stopper.
Steps:

1 Pull out the old pop-up sink stopper.

2 Use an adjustable wrench to remove the pop-up lever from beneath sink.

3 Loosen the compression nut connecting the trap to the vertical drain pipe.

4 Use pliers to loosen the tailpiece.

5 Unscrew the pop-up drain assembly from the sink strainer.

6 Use two screwdrivers from above to prevent strainer from spinning; loosen strainer nut from below.

7 Pull out old sink strainer.

8 Place plumber's putty under new strainer; set strainer in sink.

9 Tighten nut from below to secure new strainer; clean away excess putty.

10 Thread new pop-up assembly onto strainer.

11 Cut tailpiece to length using tubing cutter; coat threads on tailpiece with pipe dope.

12 Fit tailpiece between trap and pop-up assembly; thread tailpiece into assembly.

13 Tighten compression nut on trap to lock tailpiece in place.

14 Insert new drain lever between pop-up assembly and perforated linkage.

15 Place stopper into sink drain hole.

16 Test stopper to ensure it glides up and down smoothly.