Replacement should include the following steps:

Loosen the lock nuts on the P-trap.
Slip the P-trap to the side.
Remove the drain flange.
Clean the drain hole top and bottom.
Apply putty to the bottom of the new basket strainer flange.
Set the new flange into the top of the sink drain hole.
Place the new washer on the lock nut and tighten the drain flange securely into place.
Replace the tail piece and recouple the P-trap.

Process/Skill Questions:

What safety precautions/procedures should be followed when replacing a kitchen sink basket strainer?
What are the parts in a sink drain line system?
What is the function of the parts in a sink drain line system?
What tools and materials are required for replacing a kitchen sink basket strainer?