How can we be done so that bitcoin prices become more stable?
No it can't be done. If its stable then trading bitcoin will be boring and the market will not be as lively as in the last couple of years. Maybe when institutional investors gets it, or perhaps when the ETF is approved but its still debatable. One factor though that the price will not be stable is that this market is based on speculation, meaning its very unpredictable. Perhaps you should embrace the price volatility and make the best out of it, just saying.