1. Start from a small level
2. Get enough savings before
I don't understand what you mean by small level but if I may say, now, in Bitcoin, there is no small level. Just dont wait for it, buy in any chance you get.
And again, you don't have to wait till you save up, $5 dollar Bitcoin now can worth thousands in years to come. Therefore waiting to get enough savings before buying equals to not buying at all. Or even missing out buying with a good price.
I don't think that he is talking about the price of bitcoin he's talking about the capital that you use on each one of your trades, it is very common for newbies to use all of their capital on their trades and as soon as they make a mistake they lose so much money that they get desperate and begin to make additional mistakes.
It is way better to begin your journey as a trader or investor with a small amount of money that way if you happen to make a mistake that mistake is not going to be as costly, you're not going to get as upset and finally you are going to learn something from that experience something which is invaluable in the markets.