First trace out the design you have chosen on the fabric using tracing paper and carbon. Stitch the outline and then fill in the design with running stitch leaving very little space. The model is shown here to get the idea of the stitch. The stitch shown on the right side should be longer and the space in between should be minimum possible.
Take two strands of thread, tie a knot at one end and start stitching. Take the needle up from below the fabric, leave some space, take it down and up again repeatedly till the outline is fully done. Start stitching inside the design in the same way until the whole design is filled.