These are the questions I ask myself before investing.  This assumes you know the difference between trading and investing.  Not financial advice.

Should I invest in Bitcoin?

Question 1(Most important question): Do you think BTC will make another All Time High (ATH)?

Yes.. Carry on to next question.

No.. Don't invest, find something else.

Question 2 (2 part): Where is BTC from ATH and would I be happy with the return?  At what point would I not be happy with the return?

This question is to find the top limit of your DCA.  So for example, BTC is around 45% from ATH right now, yes I'd be happy with that return so I can start my DCA straight away. 

At $100K the return would be less than 25% which I'm not very happy with, so when BTC reaches $100K I stop my DCA and just hold the BTC.

Question 3: If price continues to drop, at what point would I get worried?

This is not asking where you think the bottom will be, this is asking when would you look at the price and think F*** me, that's cheap?. 

This is your 'All in' price.  You don't stop your DCA, you keep that going and on top of that you buy as much BTC as you can with any spare money you have on hand.

Final Question: What's my 'Exit Strategy'?

Always have an exit plan, try and make it sensible to begin with, and stick to it.  For example..

BTC ATH - sell 50% of holdings.

BTC at $200K - sell 50% of remaining stack.

BTC at $500K - sell 50% of remaining stack.

Obviously this is just an example, you should make your own plan with your own prices and percentages.

Should I invest in (insert name) Altcoin?

Question 1 (Most important question): Will this coin survive?

There is a lot to think about when answering this question..

for example, is it truly decentralized?  Decentralized coins have a longer life cycle as they can't really be stopped whereas centralized coins can be frozen or shut down. 

Is it a memecoin? Memecoins have a much shorter life cycle and if it's already had a couple of good cycles, it may not come back. 

Does it have a foundation/ company behind it? These coins come with good points and bad, foundations/ companies will push forward development of the coin, but also may fund those developments with sales of the coin (not good for price). 

Do you know the devs behind the coin or are they anonymous?  Anonymous in my opinion is not worth the risk. 

Is the coin regulatory compliant or will there be any issues with regulations in the future?  Think Monero, great coin with privacy but every government on earth is trying to crack it and ban on/off ramps.

Even after you answer all these and more questions you think of, it's still impossible to know for certain (think Luna and UST).  Really you are just trying to root out the more risky coins.  So after thinking about all that..

Yes.. Carry on to next question.

No.. Don't invest, find something else.

Question 2: Do you think BTC will make another ATH?

You must always take into account what Bitcoin will do, unfortunately all altcoins still move off Bitcoin.  If Bitcoin dumps, alts will dump harder, if Bitcoin pumps, alts will follow.  

Yes.. Carry on to next question.

No.. Don't invest, find something else.

From here it's the same last 3 questions as above, just swap out Bitcoin for whatever Altcoin you want to invest in.

Until Next Time, Stay Frosty!