To understand the way the application prints, it is important to define a number of concepts such as below 

Message
A message can be letters or electronic messages. A message is always based on an existing text document, which is referenced by a corresponding record in the SMH table.
This can be a primary message - text document, which is defined in a transaction or in a module. It triggers the initial creation of the message. A primary message is saved as text document with an appendant record in the table SMH.
or a secondary message - which is created to forward a Primary Message due to mailing instructions or by clicking the [Copy To] or [Send To] button on the message details panel

Technical Form
A technical form (TEF) describes the type of paper used for printing (for example, writing paper with preprinted letterhead (LTR), blank paper (BLK), or security paper (SEC). The technical form determines the printer to be used and the tray for the printout. The trays contain the various types of paper.

Application Form
An application form is a logical form on which a message is printed on. The application forms 'Original' and 'Customer Copy' are always available. These two and any other possible application forms are stored together with their long texts in the APFTYP codetable.

Form Set
A form set defines the number of messages to be printed on each application form. In a form set it is possible to define which technical form (type of paper) has to be used and how many copies have to be printed out for each application form.

Refer Article to check for PRINT - Tables and FIELD MAPPING related to printing in DOKA SAAS.

Any document created in past transactions can be viewed at any time from the contract transaction overview. Documents in TFaaS environments are shown as PDF in a separate browser tab , can be downloaded / send to local printer from there for printing purpose .

Printing in DOKA SAAS comprises of three steps 

• Maintaining Form Set
• Maintaining Printer Configuration
• Test Print System

Maintaining Form Sets

Transaction DBIAPF is used to maintain form sets.

The following Operations are allowed in the transaction

1.To create a new Record

2.To Modify/Update an existing Record

3.To delete Unwanted Record

4.To log Modifications

Follow the below GIF to Maintain Form sets in DOKA

Maintaining Printer Configuration

Transaction DBIPRC  is used to maintain the existing printer configuration on Unix systems and client / Server installations.
Printer configuration is adapted to the bank's current printer environment during the installation phase. The printer configuration is stored in file  path ini/prtcfg/printers.xml. Important Fields are the Format and Printer PPD Select option

Format
The Format column offers the options PS (PostScript) and PDF (Portable Document Format).
The PDF format leads to the creation of PDF file, PS to PostScript files which are handled further using Script.

Printer PPD
For the PS format, under Printer PPD the PPD file (PostScript Description File) has to be selected. In a standardized form, PPD files describe the features (e.g. trays) a printer has and the command sequence used to address them.

The printer manufacturer provides the PPD files. When installing printers under Windows, these files are usually installed in a Windows subdirectory and are available on the printer installation CD.

The PPD files have to be available in directory ini/prtcfg.

Follow the below screen shot to maintain printer configuration

Test Print System
Transaction SYSPRT
The purpose of this transaction is to check, if the printer control works completely (i.e. continuously from the document in the application as far as to the print output on the correct paper out of the correct bin of the correct printer).
For this, the following data can be entered:

1.User ID
2.User Group ID (can be defaulted from the user)
3.Entity ID
4.Technical Form
In addition, the Defaults for Technical Forms are defaulted from the printer configuration of the Task Manager (MGRTSK) and can be specified differently here for testing.

Follow the below gif to Test print