'A picture says more than a thousand words'
It is scientifically proven that people's levels of intelligence are mainly based on their genetic predisposition. The level of general intelligence cannot be altered later in life. What can be improved, though, is the performance of your brain. Scientists have found out that the human brain can be improved until late in life. This is called neuroplasticity.
To improve the performance of your brain, you can use different techniques. One of them is called the 'Loci Technique' which can be used to memorize e.g. the storyline of an important presentation. It brings your content into a fictious structure.
This is how it works: While you walk along a specific route (e.g. your way to work), you place imaginary pictures of the things you'd like to remember on different stations along your path. After you have walked the path several times, you will be able to do this in your head and thus remembering the storyline of your presentation even weeks after it has taken place.
Do you have an important presentation coming up or a learning topic that you'd like to remember? Try out the 'Loci Technique' to boost your long-term memory.