As others have offered, we (mostly) all have had this experience.
One solution is simply to just practice more and more often – practice teaches our mind (or builds neural nets) to do any skill we care about.
This pretty much goes for all of the memory techniques. Anyone can learn almost any of the basic techniques and instantly impress themselves and a few friends but it takes real work to master any one of them.
What we really want at a minimum – and I don’t always meet this criteria – is to know the technique and call to mind the necessary mnemonic (palace, peg words, etc.) without effort as well or better than we can do simple arithmetic sums or multiplication tables.
At first, many people believe they have “learned” the technique when they can explain it and use it with explicit effort – the goal is to use it as naturally as walking or talking.
In the meantime, remember: Any which way you can! including:
- List item
- Break it up as others have said
- Find rhymes or puns for all or the parts of the word
- Anchor it to SOMETHING else you can remember (many people forget this step when memorizing long lists of factoids like the geological ages, uh, which is an epoch, an era, a period, duh…I forget – no, I didn’t really learn that part.)
My best example is a medicine I take (prescribed) for cognitive enhancement:
Modafinil – I had a devil of a time getting the middle consonants in the right place until I (silently) started calling it “Mo-Daffodil” – this only worked because putting the N for NIL at the end wasn’t troubling me once I had the start and the rhythm of the word.
Long lists are HARD unless you anchor (i.e., link them to an anchor) them to other ideas or facts you know well OR unless you review them regularly.
So not just learning the words, but also the order, and also giving them some “life” that YOU find interesting and relatable.
I am pretty good at this stuff but no where near the level of people who compete and practice all of the time.
This is much like being a basic tournament chess player (e.g., C-level). You can beat most anyone that doesn’t play in tournaments (or equivalent) but there are B, A, Expert, Master, Senior Master, International Master and finally GrandMasters above you.
Keep practicing. Find what works. Work at or change what doesn’t.
And then work at what works until you improve it to the next level.
I love the term “Level Up” to describe this effect.