Don't stop

If you want to stop a behaviour then focus on doing something else and realise that anything worth doing is worth getting wrong at the beginning.
Did you drive well the first time?

The way to stop being Self Conscious is to practice 'Other Consciousness'

Block

What is your block made of?

If it is a mirror or wall why not make it a window and experiment experiment with expanding or changing the metaphor.

If you explore your metaphor look inside it to see how well it is formed: is it complete, look beyond to see if you can add to it and enrich it and notice how it changes and how you feel about it. Can be very powerful.

Self Talk - again

How we talk to ourselves is really important. Any hypnotist or someone who does self hypnosis will tell you that.
If I say that ' I am an idiot' then I am listening to that statement at both a conscious and unconscious level. At a conscious level I know what I mean but the message gets through unconsciously especially if I have a habit of saying it without the added value.
'My stammer' - suggests that this is a separate thing and to talk of 'cure' is to presuppose a disease.
Blushing is a good substitute for thinking about stammering.
Would you talk of 'my blush' No, these are things we do and it is worthwhile just catching ourselves up and taking issue with ourselves when we say anything to ourselves that we would not like to hear from anyone else.