I've struggled with this my entire life and from my experience, it seems that a lot of therapists aren't really skilled at helping this client in this area, at least not skills enough. So I've had to do my own searching in addition to go to therapy. Maybe we all have to somehow find our own path towards self-acceptance.

For me its not that I was afraid of being egotistical, but I was and still am afraid that I would be lying to myself and make a fool out of myself for believing something that is not true. I think we all have to get to the bottom of why we feel the way we do.

What your friend did sounds like affirmations. Some people really like affirmations, I've done them before, but I stopped for some reason I can't remember. I think sometimes they can be helpful. Some people say you need to keep repeating them over and over and eventually you will start to believe them. For me, that didn't happen. I think if the affirmation is not so extremely different than what we believe about ourselves (in other words it sounds more realistic to our minds), then it is more likely that it will be easier for you to adopt it. I'm not so sure about affirmations in general though. I personally feel like they don't go to the core of why you feel the way you do and it still is kind of like basing your own self-worth on certain standards or expectations (that either we or others put on ourselves).

I still think first examining why it is you hate or dislike yourself, may really be helpful. Like really be specific and honest, write everything out. But its probably better to do it with a therapist or some other trained professional because it will probably be too much to do on your own. But I don't know what kind of therapist you have and they may not agree with doing this. I think part of this is being able to honestly look at ourselves, the
"good" and the "bad" or "light" and "dark", and to show yourself acceptance. I think maybe it comes down to us doing it for ourselves. Making us ourselves the authority, not depending on someone else to do that for us. Realize that all of us have parts that are considered unsavory, and that we can show ourselves compassion. I think it helps to put things into context. Realize that those parts are also probably wounded parts from our childhood or through other things that have happened to us, and there are ways of healing those parts. Have you ever done any kind of inner child healing? Its kind of a spiritual concept, but I've done some with a schema therapist before. I think there are techniques in other psychotherapy modalities like IFS therapy. Also doing shadow work (Jungian therapy) may be helpful. And There is also this technique called Inner Bonding that might be helpful. This is a video about it:

But as I am thinking about this, maybe there needs be a balance where we work on healing the wounded parts and then also appreciate things about ourselves. I just think doing the typical things like listing out positive things or doing affirmations alone, isn't enough. Its not bad to appreciate things about ourselves, to like things about our appearance, intellect, physical capabilities, talents, etc. I just think maybe this needs to also be balanced with an unconditional self-love that is not dependent on these things, and while I'm still figuring out exactly how to do that, I think part of that process includes doing some of the things I mentioned like identifying the "unsavory" aspects and practicing compassion (And I don't think there is one exact way of doing this, there may be several that are useful such as the ones I listed above, and there are probably a lot more). Does that make sense?