While it is always risky to invest in any asset there are different methods and technics to dampen the risk involved.
One famous and widely know effect - also disputed by some academics - is the cost average effect.
The cost average effect claims that diving a larger sum and investing those equal installments of a fiat money each interval will be superior to a one off investment.
So if the price of an asset goes up you buy automatically less of it and if the price of the asset goes down you buy automatically more as you invest each month (e.g) the same amount of money.
While some academics argue that in a bull market, where prices increase heavily over one year, a one time investment at the start of the year or in volatile market, where prices crash down and hence present a buying at the dips opportunity, outperform the cost average strategy, I believe they do not get the point.
First of all many of us simply do not have the possibility of a huge one time investment, hence there is no way to do it different then (monthly) installments.
Secondly - and more importantly - how do you define when the market is down, cheap, at its bottom or expensive and topish?
If you are willing to take the risk, you might try to do market timing and get all the return possible.
But in my humble view the major problem we "normal" people encounter doing investments is not to miss some gains but to loose our investment / pay a too high price for it. So usually one makes the decision to go for an asset like shares, funds or even crypto to some extend. But how do you know if it will be cheaper or more expensive next month?
So I would advise everyone to consider the cost average approach of investing...
Here is a very good summary of the academic discussion of the cost average effect:
The US already has a very dense stock and fund ownership, as does England and Canada. But many other countries, especially European countries and emerging markets have a very poor distribution of stock ownership.
So given superior long term returns of the financial markets vs. savings accounts it seems very clear that most people are put away by the possible associated investment risk - and this is of course not a good thing for those people.
While many of you probably will find that investing in the "old" financial markets is not such a good idea, I argue that the cost average effect could also work for alternative investments, especially crypto investments.
So it comes down to the same...
Of course in a bear market cost average effect will always be superior to one off investments and hence I could now claim look at crypto from the start of 2018 until now.. but this would be unfair.
Looking at time spans form the start of 2017 or 2016 of course, one time investments would have been superior as crypto prices doubled nearly every few weeks...
But as we are now living in a new and very volatile crypto world and nobody knows for sure where price will be in one month, one quarter, one year... what would you tell a friend who comes to you and asks you if he should invest a part of his hard earned savings into crypto at this very moment?
So of course first step would be to understand if he really knows about the risk he is taking by investing in cryptos at all and if he really only invest what he can afford to loose... But if all the boxes are checked and your friend does not simple invest some gambling money, monthly or quarterly installments will definitely damp the risk of your friend investing at the top of the market.
In financial mathematical terms this of course makes no sense as you would only invest in assets that you expect to increase in value over time, so an investment as early as possible will academically always be better.
But reading Kahneman's Thinking fast and slow shows that our brain and mentality suffers much more enduring a loss of say 100 USD compared to gains of 100 USD left out. So everyone that is in this unfortunate position to be asked for financial advise should keep that in mind. Your friend has mentally to feel fine with his investment - in all possible market environments - or at least in most.
This is of course by no means an investment advise! Crypto and other investments are associated with very high risk, total loss of your investment is definitely possible. This article about general investment technics/methods should only teaser you to study and read more to find the right approach for you.