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I think there are only two method that I know of which is lump sum buy and the DCA method. You mentioned buying the dip but this is also a lump sum buy that is done when price retraces after an upward movement. It is different from buying using the DCA method because it involves an instant order whereas the DCA is a continuous buying process that is done weekly or monthly as the case may be. Maybe there is further distinction between between buying the dips and other forms of buying that is done at once for which I consider less important so as to avoid memorizing too many things. Maybe for academic purposes, such distinction might even become necessary and there is nothing wrong about it.
A combination of both methods is possible but it requires someone with experience and discipline to do effectively. I will not recommend that for a newbie to avoid being emotional about the whole process, rather I will suggest focusing mainly on the DCA method that is easier to follow and produces outstanding results when followed dutifully. However, no matter what method is adopted, some level of effort is needed to be able to follow such method with a sense of responsibility.
Just because you do not recognize and/or appreciate the practicality of buying the dip does not mean that it does not have its place and/or benefits.
For example a brand new person could come into bitcoin right now, and he already knows his budget. He has $9,400 that he can buy bitcoin, right now and he also has about $2,600 that is going to be available over the next six months. So that is $12k over 6 months.
He could buy $9,400 right now at $68,300-ish, and then just DCA with the other $100 per week over the next 26 weeks, or he could set aside some of his $9,400 to be included in his DCA amounts or to set some of it aside for buying on dips.
Let's say that he decides to lump sum buy right now $4,700 and then maybe he sets up 17 buy orders every $1k dip from $67k down to $50k, so each of them would be right around $276.50, and so they would be buying on the dip if they were to execute, and if they do not execute and the BTC price moves up rather than down, then maybe after a certain time, he might choose to remove those buy orders or maybe he moves them up. to higher prices (but they would still be buying on dips.. and whether that is practical or useful might not be agreed about whether that is a good idea rather than just lump sum buying and/or adding to DCA... and the mere fact that someone wants to employ that third technique makes it a valid technique even if it may or may not be one that is as effective as other techniques.. in part depending on what the BTC price ends up doing, which is not very knowable in advance.
Most users are quite becoming sceptical whether if the other approaches to investing are efficient just like the DCA approach. It is good if we justify the fact that any strategy implemented must become profitable to the investor. The sole reason for why strategies are discussed is to make it easier to accumulate in our convenience, maximize our profits by accumulating better amounts of Bitcoin and probably to those who are not financially booming.
If we are to look at most wealthy investors or firms on strategies at which they invest is through the DIPs, which doesn't makes it ineffective to earn profits but it's a standard at which they find compatible. Everyone is entitled to his own pattern and most users who would understand the concept of bitcoin investment will know that all applicable strategies can be implemented on accumulating Bitcoin on one goal setting (the DIPs, lump sum and DCA all together) just like the example given by @Jay.