My first worlds, Justin Weber showed me this trick, and I loved it so much I made him teach it to me. It's still my #1 favorite Tower trick, and any time someone asks me if I can "do eiffel tower" this is the trick I throw.
Let's learn it.
Step 1: Step 1
Start by throwing a breakaway , going under your freehand, and around your throw hand wrist.
Step 2: Step 2
Bring the yo-yo up between you and the strings, and mount on the bottom string.
Step 3: Step 3
Slide the string off your throw hand wrist onto your throw hand finger, and undercut the yoyo.
Land on the front string.
Step 4: Step 4
Slide the first segment of string off of your free hand index finger.
This will get you a green triangle.
Keep the other segment (the one you didn't slide off) open using your index finger and thumb.
Step 5: Step 5
Slide the green triangle over to your throw hand index finger, and stick your throw hand thumb behind it.
There should be one string segment between your thumb and index finger.
Step 6: Step 6
Swing the yoyo up in front, and mount it onto the bottom string.
Step 7: Step 7
Drop everything off of your free hand.
Step 8: Step 8
Insert your free hand index finger directly under your throw hand index finger.
There should be two string segments on the side of your free hand finger nearest your throw hand, and 3 on the other side.
Step 9: Step 9
Undercut and land on the string furthest from you. (Front string)
Step 10: Step 10
There should be two string segments on your free hand index finger. Pinch the one furthest from you, and slide the one nearest you off your finger. Also drop the string segment off of your throw hand thumb
Step 11: Step 11
Pull apart your hands, and an Eiffel Tower will form.
Step 12: Step 12
At this point, you can drop everything and end up into a sleeper, or any dismount you like.
This is the one I like to do.
Bring the throw hand in a circle around the yoyo, starting towards you and behind the yoyo.
Step 13: Step 13
After making a complete circle (or two or three) slide the strings off your free hand.