In this tutorial, you will find how to create waving flag vector using illustrator. A Turkish flag will be drawn as an example. Dimensions are chosen with some sense of proportion.
how to make waving flag in illustrator | Turkish Flag
How to remove drawings outside of an artboard in illustrator?
This explains how to delete objects outside the Illustrator artboard. Also, the export methods of your vector drawing are shown. You can export your file as a raster image or vector file using these methods.