Many people think meditation is to make the mind a blank in a very relaxed way, but in reality there are few people that can accomplish this for more than a few seconds.
Concentration meditation is much easier to do and will give you faster results. Instead of trying to make your mind a blank, you pick a single point or activity to focus on.
A simple exercise in this is to get into a comfortable position, lower the lights a bit and look at a small object across the room. Try to pick something that is small and away from anything else that might distract you.
Fix your eyes on the object and think of nothing but the object. It’s just you and the object, nothing else exists. Do not move your eyes or even blink. Just focus on the object. If you are doing this right you will notice a change in your perception.
Your vision will become tunnel like and only the object that you are focusing on will be in focus, everything around it will become fuzzy and start to fade away. You might even experience an absence of color, everything turning to black and white.
At times you will notice that your depth perception has increase dramatically to the point that you notice little things that you have never seen before.
Maintain this concentration for about 5 to 10 minutes, and then give your eyes a rest. You will feel rejuvenated and calm at the same time. Practice this once or twice a day and you will find that your memory will improve and your cognitive skills will be sharpened.