Hello Kaan,
Orange peeling is caused by the paint not being warm enough during the application, whether you airbrush or use a spray can. The paint should be at room temp. or above. You can warm up you paints by running them under warm water, but don't make them to hot. When warming a paint can, hold under the warm water, then grab it and shake it. The can will become cool again, then hold it under the water again, shake. Once the can becomes warm the paint should be ready to go. Hope this help some and good luck with your next project.
Edit: When spraying, put on a light coat. Wait 20 mins then do another light coat. Again wait 20 mins, then spray on your finial wet coat. The light coats give the wet coat something to hold on to.