This knot resembles a three-leaf clover and is a symbol of good luck. It's the perfect symbol for St. Patrick's Day. This knot combined with the double knot can easily form a decoration cloverleaf knot keychain.
You will need at least 12 inches length of 2mm satin cord.
Step 1. Form the letter M with the string and hold in place with pins. (See picture below)
Step 2. Take the right bend in the “M” and tuck it under the left leg of “M” and fasten with pin.
Step 3. Take right strand again and make a figure 8 loop the top one goes into the loop just formed in the previous step. Fasten again with pin. Also fasten the other part of the 8 with pin.
Step 4. Take the left strand slip it through the first figure 8 loop.
Step 5. Take right strand again and thread through original bottom loop from the bottom.
Step 6. Finally take the same strand double back and bring it through the top loop again from the bottom.
Step 7. Tighten string to form the knot. 
You can also learn more on how to tie different knots from these books:
