How do I create data pre-processing for a template?

In order to create the data pre-processing for a data record template you should follow the next steps: 

1. Go to the task details screen, by pressing task details button
2. In the drop-down menu select the Templates option 
3. Select the template you want to create the data record view page for, by clicking on Details button
4. Select the option Pre-processing
5. Create the required pre-processing rules where each rule is composed of target regular expression (regex) and correspondent replacement value used to replace the target value when present
6. Press Save button

Why is the target value a regular expression?

Regular expressions or regex are patterns representation used to match character combinations in strings. This concept has been widely used in computer science due to its capabilities of express infinite combinations of characters as a pattern. For instance, imagine you want to replace numbers independently if it's 0, 1, 2 or 938345 with a string "NUMBER", you could use the regular expression "[0-9]+" to perform this task.

You can find more information on Wikipedia or Rexegg.com.