Most people can’t just sit down at a sewing machine and create any shape they want, for most it takes practice to fluently create those amazing shapes. But before you get to the sewing machine you should sit and practice with a pen and paper. I personally use the Paper app on iPad, so I can delete unwanted drawings and not feel like I am wasting reams of paper while I perfect how to draw a shape.
Once I have gotten a good feel on how to draw the shape and it is flowing fluidly, that is the time to go to the sewing machine and start stitching. You will be amazed by how easy it is now stitch a pattern. Give it a go today and let us know how it went for you.