To manage finances in investing in cryptocurrency, I think it makes no difference from investing in fiat currency, that is, don't invest your money in just one investment, try dividing your money into several investments that have a good future, even though investing in your view is very convincing.
Obviously there's a lot of similarities, but the thing with crypto though is that it went crazy in the last 2 years or so and people started to jump on the bandwagon and thinks that its going to be a easy ride for them to make money here. They don't understand it, they quickly invested on scam ICO's and other stuff that makes them lose money in the market and blame it on crypto.
But upon closer look, you will notice one thing, they don't follow one of the OP's advise:
Rule #1: Invest when you understand it.
We can't really reiterate it. Everything in investment started on your understanding on how it works. If you are not ready then by all means, don't throw your money in the market.