This is how you tie a Sheet Bend. This knot is neither strong nor secure. This knot is for tying two ropes of two different diameter
Create a bight in the end of the of the rope to be tied.
Take the second rope and tug it up through the bight.
Pass the working end beneath the bight.
Tuck the working end beneath itself in such a way that both short ends are located on the same side of the completed knot.