Figure 8 knot.

first you need to begin with an end of string in each hand then you bring your right side of the string over top of the left side of the string...








Bring the string on top behind the other side of string shown in the picture beside...

With the piece of string that you just put around the back now needs to loop over and go through the hole but through the side that is facing you...

pull tight and that is what you should have!!

Thank you for ready and remember practice makes perfect and soon maybe you'll be sailing an optimist yacht!!