Regarding recall from long-term memory: Write it down!
By this, do you mean that the act of recording the information will itself improve recall, independent of later reference to the recorded information? I recall hearing at least anecdotal evidence for such, but I'm not sure how well documented the effect is.
Of course, even without such an effect writing important things down in general is a good habit to acquire.
I was actually thinking more about looking it up later, i.e. extending your long term memory via paper and pencil.
Although I can also report that I remember stuff better if I wrote it down.
Transhumanists have high hopes for enhancing human cognitive abilities in the future. But what realistic steps can we take to enhance them now? On the one hand Flynn effect suggests IQ (which is a major factor in human cognition) can be increased a lot with current technology, on the other hand review of existing drugs seems rather pessimistic - they seem to have minor positive effect on low performers, and very little effect on high performers, what means they're mostly of therapeutic not enhancing use.
So, fellow rationalists, how can we enhance our cognition now? Solid research especially welcome, but consistent anecdotal evidence is also welcome.