Remember that you are not your Inner Critic, it's only one perspective within your mind. This creates separation already. Then strengthen it by creating some DISTANCE between you and your Inner Critic. Imagine the Critic being located outside of you, to one side, not taking the same space as You (in your central aware place), and really FEEL that you are separate.
These 3 simple steps will create the necessary distance from your Inner Critic, so you can then look at its statements more objectively, and re-frame them in a more compassionate way.
When you create separation between you and your Inner Critic, you will more easily separate from what it's saying too. You won't as easily take its viewpoints as proof of your inadequacy, but rather as just one perspective that you can choose to consider or disregard, depending on how constructive it is.
You can then start to think of what else you would rather believe about yourself and your life. And look for evidence of *that* being the truth. This will be so much more empowering, and will help you create the life you really want to live, feeling good about yourself and your path in life.