Now that you have your "two-under-right-one-under-left" pattern in the weave rope, start pulling it. Again, pull TOWARDS yourself. Don't pull to the right or left. Keep your feet on the drum to steady it. As you pull it firmly, it will cause the tension ropes to cross over each other, thereby increasing their pull on the skin of the drum.
I find it best to grip the rope as close to the drum as possible, increasing your force directly on the point where you want it. If you grip your weave rope too far back from the drum it makes it VERY hard to make the tension rope cross. Once they are crossed, they SHOULD lock into place from friction, but may not if you don't pull hard enough.