User Exits in MDE

Hello All,

I have a requirement where i need to change LM51 MDE screen. I just want to add one display field on the main screen and want to add one check in the program.

I believe we can do it by two ways..first is to create a customized program just like LM51 and another is User Exit. I want to do it by second option. I found a screen exit for the same.

But I dont know the exact steps which i need to follow now.

Can anyone fwd me exact user exit steps?

Thanks in advance,

Pranav