Find Exits for a given transaction code

Find all the customer exits available for a particular transaction code in 2 simple steps:
For instance, we need to add custom fields in transaction code IW31

1. Transaction code 'SE93', enter transaction code and display. Copy Package.
   
2. Go to transaction code: SMOD -> Utilities -> Find
   
3. Enter Package and then Execute.

All the available Exits will be listed along with the description.

Now you can choose appropriate exit as per your requirement.
Exit IWO10018 is identifie for adding custom fields in IW31.

P.S. This is a very frequently used method for finding package of tcode but not helpful.
Tcode -> Menu-> System-> Status.
Double click on Program name and find Package from Program Attributes.
Try finding screen exit for IW31 with this method, you will end up getting no result.