This isn't how I implanted them, but you could try using a spaced repetition system such as Anki:

http://ankisrs.net/

Whenever you saw a card corresponding to a phrase, you could challenge yourself to come up with a situation in your recent past which you could have used the phrase.

Alternatively, you could describe to me what stigma you tend to experience and I could tell you which phrases to use and how they apply to your situation. If you give me your email address, I can trivially send your future self a few reminders on what you should be keeping in mind (I use http://www.boomeranggmail.com/ for sending delayed emails). And, I'm extending this offer to anyone, not just Blueberry. If people are too embarrassed to discuss the stigma they are harmed by under their Less Wrong usernames, they can create shill usernames or email me with a shill email address at dreamalgebra on google's email service.

Also, I wonder if the system can be tweaked so that it doesn't undercut strong positive emotions which are in the harmless-to-useful range.