Meditation is pretty straightforward, and can easily be perfected through practice. It's all about simple calmness, focused energy, mindful thought and a matter of conditioning yourself to let go of thoughts of desire and to tolerate discomfort. Soon you'll find yourself coping easier with pressure, more relaxed in your demeanour and mindful of your actions.
The secret of meditation is to remove the unbalanced emotions from your mind by focusing on a settled mindset. Keeping mindful of your breath is the most effective way. Once your mind is settled and calm, it's much better for dealing objectively with any problems and other thought processes going on in your head. Once your mind is relaxed the body follows.
There are many different styles and techniques for meditation, many connected to religious practice, particularly Buddhism, but meditating is actually based on a simple technique and suitable for anyone. Sore and numb legs are common if you're not used to sitting cross-legged. However, part of the challenge and purpose of meditating is to learn to cope with discomfort by ignoring it or placing it in perspective to greater discomfort. Gradually it goes away if you persist. Gently stretch them out in front of you and patiently wait for the blood to circulate again. Novices can start out by meditating on a chair to avoid painful legs.
If you have time, or perhaps just interested in spending a few hours away from the hustle and bustle, you can learn meditation techniques from English speaking teachers at the Vipassana Meditation Center (Wat Mahatat). Located close to Sanam Luang, the Wat Mahatat temple complex has a school where Buddhist monks have been giving classes in meditation for over 40 years. The main teacher speaks good English.