9 Tricks to build more
The Galatea effect says our performance rises when we expect realistically better from ourselves. Low expectation = bad performance = low confidence.
The Pygmalion effect says our performance depends on how much others expect from us. Low expectation = bad performance = low confidence.
Low confidence comes from not seeing progress or a belief there is no progress. Set small targets and monitor your growth. Only rely on that growth for "sourcing" your confidence.
Take risks and expose yourself to new and challenging situations to overcome low confidence. Familiarity reduces the threat and builds confidence. The mere-exposure effect says the more you are exposed, the more you like it. To overcome anxiety, prepare well so you know you can deal with uncertainty.
Self-compassion is showing yourself kindness and love by not being to strict or expecting unrealistic achievements. It is accepting that failure and anxiety is acceptable and you can use effort to progress.
Social media rewards success and not failure. People display a superior version of themselves and filter out the negatives. So comparing yourself makes you feel worse about yourself because your reference point is exaggerated "good". Avoid comparing with others' achievements.
Everyone doesn't have the same goals for productivity or what they want in life. Instead of adopting other people's standards, set minimum criteria for yourself and work toward those. You might just be satisfied on your own.
Confidence in skills, memory, capacity to execute, etc., depend on meta-memory which decides what you know and don't. It can go wrong because it doesn't check your actual memory, just bits of it. To minimize grand failures, introspect and get realistic about what you know and don't, so you make choices according to your actual capacity.
Ditch all beliefs that everything is set in stone or everything is about effort. It's a mix of both. Tell yourself you can improve things under your control and not waste effort on things you can't control. Embrace uncertainty and work through it as it comes to you.