For many years people believed the following:
10% of what we read
20% of what we hear
30% of what we see
50% of what we see and hear
70% of what we discuss with others
80% of what we personally experience
95% or what we teach others
However, a lot of people have said that the preceding is not true.
But from my experience, I remember things better when I write them and I remember things better when I write them by hand (as Jeene said).
And the best way to remember something is by doing it rather than just seeing or hearing it.