Renate,
I sit with the emotion as long as I can. I'm not successful every time, but I am most of the time. And much of the time, I'm just getting a piece of it, not necessarily all of it. I would keep doing it until you move it through to grief, then correct the belief.
Here's what I've done with the "not feeling 'good enough'" emotion:
I start with feeling it. I let the fear manifest in my body as best I can. Sometimes, the fear makes me shake. If I'm not shaking, but I can tell that it wants to shake, I'll kind of feel which parts of me want to shake and I'll let them shake. It's kind of like spasms, but not so uncontrolled. What's happening is the energy of the fear is getting expressed in a safe manner through shaking. While I shake, I'm strictly supportive of it. "I know you're scared. I don't blame you one bit for being scared. I've been scared like this, too. All is well. I'm right here. You do what you need to do. I accept you unconditionally." Once I don't feel like my body wants to shake anymore, I know the fear is pretty much done being expressed. That's usually when it moves into grief. Sometimes it's anger that starts the process of not feeling good enough. Anger toward myself for not being good enough, anger toward my parents and God for not making me good enough. So check to make sure anger's not there. If you're at fear, the anger probably isn't there, but it could be. Once you move through anger and fear, you'll move into grief. Grief is usually crying. Be very sensitive to the feeling of needing to cry, and as soon as you get the sense that you need to, give yourself fully to crying. If you have to start forcing the cry to get it to start, that's fine, too. Be just as supportive while that part of you cries.
When I reach the crying stage, I try to see if something will increase the crying to make it more fully express itself. For instance, I will hug that part of me and that will suffice sometimes. Sometimes, I'll have God hug that part of me in an unconditionally loving way. That one really seems to get a strong crying reaction out of me, depending on the issue at hand. Eventually, when the crying's about done, I start talking through the incorrect belief and then the accurate belief. I use reason. Here's an example:
"So you feel like you're not good enough? I can understand that. Do you know where that comes from? Judgment. And a standard to judge by. Did you know God doesn't have a standard? He's unconditionally loving, meaning there are no conditions on His loving someone else. That's what real, true love is. Everything else is a counterfeit." (All the while, that part of me is responding to me when necessary. I do most of the talking, but when that part of me needs to speak, it does. If it needs to ask questions to really get a handle on why it's upset or scared or sad, it can do that, too.) "So, did you notice that nothing you can do can make God love you, because He has no conditions on His love? In other words, there's no way to be 'not good enough," because you don't have to be 'good enough.' In fact, God doesn't have a standard. He's not judging you or anyone else. Never has. We're the ones judging us and we got our standard from our parents, our feelings, our society, and our religious ideas. But really, though, there never was an actual standard. Once we drop our standard of worthiness, we are neither good enough or not good enough. We're neither worthy or unworthy. We simply exist. And you know what? We can actually feel our own unconditional love for our self at that point. It's natural and it's always there. Judgments get in the way of it. And when we feel our own love, we feel God's love, too, because they're practically the same thing. We're His kid, so we have all of His traits, like kindness, contentment, happiness, and His unconditional love. We just have to remove our standards that we acquired or made up. They're not real. They never were. We don't need to be loved--we just need to stop blocking our own love and God's love. Then we'll feel our contentment and happiness. It's really that simple, but it takes sometime to find all of the judgments. For now, let's just deal with your judgment. Which would you rather do: judge yourself and feel awful, or drop all judgments and opinions and standards so you can feel happy and content?" Those inside parts of me always answer with the latter. "Alright, well let's do it."
Oh, I like to tell them about the neart-death experience part where God makes people relive what they did to others that hurt them. They feel how they made the other person feel this time, which causes them to feel great shame. They say, "That was so bad, so wrong." God responds with, "No no, not good or bad, not right or wrong...just a lesson learned." Immediately, all of their shame drops and they feel their own unconditional love and God's unconditional love. They say it's unlike anything they've ever felt and extremely powerful--life-changing. They realize that they were judging their self, but God never was. Once they dropped judgment, the suffering ends. All they had to do was drop judgment. It's so simple, but very hard to do.
Another one I use is: "So when you punish yourself, you feel worse. How do you treat others when you feel worse?" Inner child: "I treat them worse." Me: "How do you treat other people and yourself when you feel good?" Inner child: "I treat them and myself more kindly." Me: "So that's what you're shooting for in life, right? To treat others more loving?" Inner child: "Well, yeah." Me: "So, which sounds better to you--punishing yourself by hurting your body and feeling bad, or loving yourself no matter what you do?" Inner child: "Loving myself no matter what." Then I take him through that process of getting him cleaned up and integrated.
I use that method because that's what I did when I worked with multiples. But they actually go inside to that inside world. I can only imagine it. They actually see it and see those parts of their self inside. They go there and it's as real as this world. It worked on them, so I made it work for me as best I could.
Hope that helps!