The folloiwng info may be useful for those who are new to SAP:

All Standard Scripts are in client '000'.
We have to copy them to '800'. (this is your own company define client no)
All Standard Scripts and their respective print programs are listed in table 'TNAPR'.
Ex: FORM MEDRUCK has the Driver Program SAPFM06P.
NOTE: Never make any changes to the Standard Driver Programs
   
STEP 1.
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Goto Transaction Code <SE71> and 
select from Menu UTILITIES ->Copy from Client.
Enter the Standard Form Name, It source Client 000 and the target Form Name that you want it to be saved as on your client.
Say you are naming it as zmedruck1.
Click on EXECUTE.
   
STEP 2.
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Converting form to English.
Open zmedruck1 in <SE71> With language DE.
Then goto  UTILITIES -> Convert Original Language from DE to EN.
Then you can modify the layout for example, chaging the logo, or changing the headers, or adding any new code to do some calculation etc.,
SAVE THE CHANGES AND ACTIVATE.
Then select from the menu  FORM -> CHECK -> TEXT.
SELECT your driver program name from the list adn click on COPY.
If you don't see the program name in the list then click on 
'APPEND PRINT PROGRAM' and add your program name and then select it from the list and click on COPY.
  
STEP 3: Assigning our form to the standard print program.
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Start Tr.Code <NACE>.
In our present case since we are working on 'Purchase order' we have to select EF and click on the button Output Types.
Then on Right hand side, scroll down and select  NEU - New P O Printout. 
(This may change for different programs).
Then Double click on  Processing Routines on Left hand side.
Change from Display -> Change Mode. 
Give your form name (zmedruck1) for printoutput and SAVE.
   
STEP 4:
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Start Tr.Code <ME22N> since you are working on Purchase order and click on print Preview to make sure your layout etc., changes are OK. If not again you have to make the changes accordingly.
   
If every thing looks ok then you can print your form.     *-- Ram Prasad

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