If you want to grow up the amount of Bitcoin, but without having to enter the realm of altcoin. Just trade BTC/USD and USD/BTC all the time, long and short time. example; buy BTC at $3000, and sell it for $19000. Buy again when the price going down at $6000 and sell again $7000. always going grows up your money and your bag BTC. If you want to hold BTC, try to split the balance. so you can focus at long-term with half of the capital/fund and use half to short-term trade.