Naturally, meditation is just to relax. It is the state of no mind, so laughing is introduced here. Just laugh. Yes, just laugh. You might be curious what you are laughing at. Here is the explanation.
Laughing without any reason is happiness. Seriously, if the happiness has the causes, it can disappear when the causes are eliminated. So just laugh, then you will really laugh. It may feel weird at first but if you are consistently laughing everyday and every moment of your daily life, your immunity will rise to you.
When you laugh, you cannot think. That is why it is said that it is the meditation. You laugh so deep that no mind comes to you. You enjoy it. You allow yourself to go with the flow of laughing. You are at the very present moment. There is no ego there. You disappear with laughing. Now you are no more than laughing.
This can happen when you let yourself to the action you feel in love. If you really dance, there is no mind. If you really write, there is no mind. If you really do something with flow and surrender to what you do, there is no mind. Mindfulness happens.
Laughing is the result of the creativity to see the simple things new, and the relation of things that seem unrelated before. Metaphor is the great example. For instance, the great speech is like the bikiny. It has to cover the most import part but left the part that is very interesting. This idea was post on the picture of the girl wearing bikini, and I, to be honest, smile without reason.
People who can see things creatively is amazing. Photographers are always creative. Sometime you as the outsider may have no idea why they post their bodies so weird but after you look their picture, you will become awfully stunned to the beautiful photos.