The timing for surfing waves is a skill surfers need from beginning through catching the biggest waves on the planet. It is learned through practice.
The beginner catches foam waves which is good practice for real (green) waves. The idea for both is to anticipate when the wave will arrive to push the board, get momentum, paddle into it, and then pop up on it.
The foam wave has the biggest lead time for it can be seen approaching and the only requirement is to get in front of it, paddle for momentum, and then patience to paddle a few more times to get in front before popping up. (beginners lack patience to paddle in front of the wave)
In a real wave, you want the wave to arc lifting the board and when the board is at the top of the wave, the surfer paddles hard and maybe kicks to get the nose facing down. Once the board starts to slide down the wave, the surfer pops up smoothly.
The timing issue new intermediate surfers have with real waves is it takes courage to let the wave arc behind and over your head before paddling down the face. Most beginners feel more comfortable letting the wave pass and then catching it. Big mistake. A late entry usually means crashing down the face or losing the wave pocket and just riding foam.
Watch the timing of other surfers. When you know what to look for it becomes obvious. Notice that they line up where the waves arc. Then when they spot a wave they start paddling for momentum and position. They may have to compete with others in a line up, but in friendly line ups, surfers rotate.
Then as the wave approaches and the surfer is moving, never taking his eyes off the wave as he paddles, he patiently lets it rise under him, paddles hard three times and once it starts pushing, pops up.
A great trick for getting into the pocket is to push the nose of the board after catching the wave and before popping up into the direction of the pocket. This saves the need to drop down the face and bottom turn. If the wave is too big or is closing too fast, you may need to drop down the face first and then carve a bottom turn.
For surf lessons in Oceanside, see the Home Page
For a good video on catching real waves