The biggest mistake that I see people make in this terrible action is to believe that entry points don't matter much if they are buying stocks for the long term. The logic is that stocks are going to be much higher a couple of years from now so why should I be concerned about what I'm paying right now? It will work out well if I just buy right now and stay patient.
This logic almost always leads to buying too big and too fast and then, in the worst cases, leads to panic selling when the stocks go substantially lower and emotions kick in. This is the main mistake you want to avoid when you try to buy in a bear market.
There is an old British saying: 'Take care of the pennies and the pounds will take care of themselves'. That is particularly apt when trying to build a long term position in this mess of a market. Focus on good entry points now and the big gains will eventually take care of themselves.
The first thing to keep in mind is that you aren't going to time the exact bottom no matter how hard you try, so don't focus too much on that. It is best to make a series of buys and to hope that the average works out pretty well.
There are a number of emotional and psychological reasons that drive people to buy too early. One part of it is that are trying too hard to nail the exact low. Most people seem to prefer buying on the way down rather than on the way up although risk can be much less when buying after the low.
Intellectually buying 10% too early is no different than buying 10% too late but impatience and hope drive premature buying.
I'm going to use an example of a stock and then follow up in the weeks ahead as I build a position for the long term. That stock is Disney (DIS) . I have a position now which is maybe 10% of what I am aiming to hold. I'll hold that 10% and will look for additional entry points on strength rather than weakness. I see no reason to add to it now because the risk to the downside is still substantial. I'm happy to pay a higher price when there is some greater clarity about coronavirus. I'm going to watch the pennies carefully and I'm confident the dollars will take care of themselves.