I have to confess that I don't know the science behind the financial markets at all, let alone cryptocurrencies. I've only been in this environment for a little over 4 years, but I'm not a trader at all. My latest strategy is simply to buy a fixed amount of dollars in a major currency. And I'm not thinking that if the markets go up, I should buy less or think about selling. For now I'm just making a small piggy bank, with a symbolic weekly amount, which many of my coworkers use to pay for the week's coffees.
People tend to underestimate what a difference small amounts can make if used well consistently over time.
That is been my "strategy" since High School. When I was still living at my parent's, I use to save all the money that I could for a important buy in the future. I might say that, many years later, I used that saving, and also big chunk of first 11 years of employee salary (I was living at my parent's so my expenses were few) to give for a entry value for buying a flat (the one that I'm living in, and paying a very affordable bank loan. Just like you said: Grain by grain... Consistently