Meditation is as individual as our fingerprints. Each person must find their own way although I highly recommend taking a class or reading a book about meditation to begin. Eventually you will find the method that is right for you if you just begin.
There is no right or wrong way.
Meditation is a time of quietness where you think on or ponder a question, a topic or a situation. Some people do this while driving a car or pulling weeds in their garden. Others set aside a time and place where they will not be disturbed and sit in quiet and solitude while they contemplate. Again, it is as individual as you are.
Meditation soothes the soul, so if it is stressful or forced, the soothing cannot be accomplished.
All and any meditation is effective just as is prayer. Prayer is a form of meditation but sitting in quiet meditation is usually not a time of asking, it is a time of giving to yourself and to the Universe.
As with prayer, the meditation can last for a few minutes or a few hours. It all depends on you.
My advice to anyone seeking to start a meditation practice is just to begin. Here are a few suggestion that will help you to get started now:
1) Find a quiet place where you will not be easily disturbed -- the corner of a room works nicely.
2) Wear comfortable clothing so you don't feel bound up or uncomfortable.
3) Sit with your back straight either on the floor or in a chair depending on your ability.
4) Breathe deeply and consciously and focus on your breathing -- the in and out of it.
5) Allow thoughts to come to you and don't struggle against them while you focus on your breath. If the thought is distracting, gently push it away like an annoying fly. If the thought is reflective and insightful, make a mental note of it for later or allow it to open to you.
6) Make your meditation time a daily practice.