In a bull market comes a lot of opportunities to profit, but it also comes with a lot of fraud, so you have to be careful not to fall victim to any fraudulent programs.
If you are looking to earn some passive income, the best way is to participate in staking programs for some good currencies provided by some reliable exchanges, where you can get some good passive profits through staking or providing liquidity to some pairs on the exchanges.
Also you can buy a coin at a very cheap price and hold it for some time until the peak where all coins are expected to rise.