In my opinion, you can participate in Bitcoin trading platforms or join online or offline trading groups. With this investment, the profit is derived from the "buy low high". Therefore, you need to regularly update the prices at the trading floor and select the appropriate transaction time. You can update prices daily on Coinmarketcap.
I think investing into btc is pretty simple. In both, I will go for ETH. You just need to buy or collect btc. But these are altcoins and they dont have much stability in market. And save it to your wallet. Not about the prices but related to the market value. After that, you wait until the price of btc to go up. Altcoins are so much and some of them are playing good part on their side but on comparison with bitcoins, I believe bitcoins take the lead always for so many reasons. After you get profit from btc you can sell your btc. So if you are planning to invest bitcoins for any other altcoins, you must review your decision. But do not join some online business like hyip program.