To an extent, I believe in the idea that you teach people how to treat you. Meaning, the way in which you present yourself produces the way in which people interact with you.
Most people see this in obvious extreme cases: if you come across a shifty, heavily dressed man with his hands in his pockets, you’re more likely to expect the worst and avoid any interactions with this individual. However, people don’t acknowledge the significance of this in more subtle cases, like a weak handshake or failure to hold eye contact in conversation with someone. For those with low confidence and self esteem issues, this is problematic as their warped view of their own worth could be giving others permission to reinforce that low view upon themselves, just as you would treat a cheap t-shirt with less care, people who view others as ‘less’ than them can sometimes tend to treat them with less respect.
Now, I’m not saying the solution to this problem would be to mask self-esteem issues by walking around telling people how great you are; that would be presenting yourself as arrogant, suggesting you overvalue yourself. Coming across as arrogant can hinder you just as much as coming across as someone with low self-esteem, because, using the previous analogy, if you bought a t-shirt you felt was overpriced, you wouldn’t be particularly impressed by it: possibly even to the extent where you’re left feeling annoyed.
If you are someone who struggles with low confidence, an effective way to battle this is to build up your competence in the areas you need to perform well and with the things you have a passion for. Psychologists have labelled this the confidence-competence loop, as those who have high competency levels tend to have more confidence. Confidence truly reflects value as it corresponds with competence, ultimately meaning those with the most confidence generally have something of worth to bring to the table.
I’ll return back to the analogy once more to make one last important note; just as a clothes designer wouldn’t take advice from a random person on the best price tag to put on the new t-shirt they’re putting on the market, you shouldn’t allow the views and opinions of others to define you, especially when they don’t know you. “Your value doesn’t decrease by someone’s inability to see your worth”.