I have found that often I will often get frustrated at information that isn't "sticky" enough to last one or two repetitions in Supermemo. If this ever happens, the first step should be to create a mnemonic, however basic or silly. But what if a mnemonic simply is not feasible? For example, what if you are trying to remember a certain point of foreign language grammar that doesn't easily conform to a mnemonic system? I think I found the answer: meaningful (pseudo)context.
When I wasn't studying Chinese very seriously, I had a hard time recalling certain grammar points. This was partly because I wasn't putting much effort into studying the language, but I was also unfamiliar with the language itself (Individual words and the "flow" of conversation). But a certain piece of grammar cemented itself in my head while I was reading the novel "After Dark" by Haruki Murakami. Although I stopped reading After Dark halfway through, I can tell that Murakami does a very good job at capturing a particular atmosphere and drawing you into it. The characters of After Dark felt like they had depth.
Later on in the book, a Japanese girl that speaks Chinese has a brief conversation with a Chinese girl. While many Chinese example sentences have slipped my mind over time, After Dark's brief Chinese conversation stuck with very little effort. In fact, those same sentences could be in a Chinese textbook and be just as forgettable as any other sentences. But once they are part of an interesting novel, those words suddenly stick in my mind. Why is this? Because I was emotionally and mentally invested in the characters that spoke; thus their words had added weight in my mind. They weren't just sentences, they were words spoken by two characters with a back story.
So how can you convert something forgettable and "unsticky" but important? After all, there will not always be a movie or book that directly addresses the thing you are trying to learn. You are left to create your own context. This is what I've been doing (With Chinese grammar or any unsticky information):
Step 1: Have a folder of assorted neat pictures (Photos/ paintings/ digital artwork/ etc.).
Step 2: Select one picture to go with that flashcard.
Step 3: Passively review that flashcard every day until the word-picture pairing feels familiar.
Step 4: Create a flashcard, making sure that you do not see the picture when being asked the question.
Step 5: Give the flashcard a few weeks to be reviewed, evaluate if the memory link is still there or not.
Why wait until you are given the answer to reveal the picture? If you saw the picture before you tried to recall the answer, there is a risk in you associating the picture with the correct answer rather than the context of the flashcard. That is one of the negative aspects of the Rosetta Stone language software. When sentences become complicated, you associate the answer with a picture rather than what you should be learning. While picture-answer flashcards are useful for nouns, for more complicated or abstract material it doesn't appear to be as effective.
What is the goal of repeatedly viewing a (seemingly) unrelated picture alongside unsticky information? Establishing context, "legit" or not. As you repeatedly view the word-picture pair, you might even create a plot surrounding the information in question.
One ancient proverb says "to the making of many books there is no end." Especially today, information is very cheap. But as Einstein said, "information is not knowledge." Having lots of information at your fingertips doesn't mean anything unless it is meaningful to the reader and is applied in one's life. Therefore, instead of procrastinating by saying "I can't learn this language until I buy this awesome "Sentence Pack ABC" that I've been told I must buy" or "I cannot learn about subject ABC until I go and spend money on a book about it," simply use one of the many free resources online and start dissecting it! Using pictures (And no doubt other media such as movies or music, although I have only tried pictures), information can (and should) be as interesting as it is important. If it doesn't seem interesting, brainwash yourself into thinking it is interesting!