Best way to HODL is buying in cheap and wait until it goes up it's value since if you can buy back once it goes down then it is good deal. But it will really depend on what you are buying if its BTC then it is good for long term but if its an altcoin then you may need to be aware that it could take months before the value it pump up even those top ranked altcoins we cannot make sure if the value will rise up.
That's why we need to make a research and analyzing and making prediction could help you be positive and not affect for those FOMOs and FUDs circulating in social media and forums.
When doing some long term hold you need to strengthen your emotional capability that can ease the time you will spending in waiting for the next bull run. Like this year it is very frustrating and it is very hard to hold when we need to sell it. But do not invest what we are afford to lose. It can vanish also, so better to choose a good coin.
If you are not ready for the roller coaster ride here in crypto and you are worried about what's gonna happen with your portfolio, I think you need to assess your situation. Because if what you invested is like the money of your savings account, then, you should really evaluate your situation if you can cope up with long term hodl without assurance of what's gonna happen. It is really better to invest in crypto the money what you can afford to lose so you are not agitated 24/7, looking every movement, can't eat, can't sleep...it will exhaust you mentally, emotionally, financially and maybe spiritually.