To enable the mode of the OTR encryption, tap the appropriate button (1) in the chat window of the program.
 

The window for entering the “secret key”, the text, which is known only to your interlocutor and you, will open.
 

At this moment your interlocutor will have to enter the “secret key” to his client
 

and wait for the identification
 

 

If the entering of keys has been correct, the encrypted OTR session starts

and the “OTR” (1) becomes active.