Concentration is very important in Psychokinesis. If you don't focus you won't get results. With my focusing problems it's harder for me to achieve what I want but with practice you get better. Just learn to disconnect yourself from the world. Don't let people or sounds bother you and try to be positive and not doubt. Doubt creates mental Blocks which I've dealt with a lot. You have to believe that it will occur and then you will see results. If You don't push your self to detach things and thoughts that seem to linger when you're meditating then you will get limited results.
The best way to get results in the beginning of meditation is to do continuous breathing, air going into the nose and exhale through the mouth. Do it in reps and feel your self losing interest in outside stimuli. Once your heart rate slows down try to continue meditating and lose your thoughts, think blank and try to stay in that state for as long as you can. Practice increasing your time of meditating day by day. There can be frustrations in your life that prevent you from doing PK well. Don't be disappointed it happens, take a break and try again when you feel better.
Your thinking effects what happens in reality so if you apply thought to create a gust and believe it will happen, it will. A simple way to create a gust is to visualize air revolving around you, then as you do that it will start to pick up then project that image of the gust in any direction and it will go to your will.
Awareness of your surroundings is important, if you pay attention to much to others or noises thoughts that don't have to do with the goal you are trying to achieve it will not happen.
Let me give you an example; You want to create a big gale or a breeze and you're tired, thinking about some troubles in your life, or it's too cold outside and you can't sense or feel psi due to the freezing conditions, thus all of these will lead to no physical manifestation of any kind. The gust just won't start no matter how much you want because you're thinking or worried about something else. Do PK in good conditions and when you're in a positive state or your PK will not work. Good Luck and don't doubt yourself, be as positive as you can then you will see that Wind PK is easy as pie.