This isn’t magic, but these helped me tremendously:
I didn’t get these things as a direct impact of magic, but as I experienced things with magic and met people from the path early on I gained confidence in my abilities in other areas.
I’m in the process of using some mastery candle magic to try and improve my career skills, which inevitably for me boosts confidence.
Probably TMI, but I have a bit of dysfunction from lack of desire (the act is a bit transactional), and I’ve been able to use hoodoo oils, foot washes, and candle magic to up my desire.
I found, too, that confidence and ability in the bedroom are related, though I guess that could depend on the person. This was at least the case for me.