Here’s a simple cheatsheet for foot position in surfing.
You can break maneuvers into two categories. Speed conserving/generating and speed killing.
Foot position for speed conserving/generating maneuvers is generally on top of or right in front of (towards the nose) the front fin on the inside (in the water) rail.
Foot position for speed killing turns, sharper snaps and cutbacks, is on the back fin, inside rail.
Front foot position should almost always be on the stringer (center) and in a vertical location where you have access without moving it to the tail.
Spray signature is a good way to tell what type of turn is happening. Conserving turns, done off the front fin, use the rail and spray is smaller and thicker. These turns aren’t your best photos normally. (weak wave, wrapping back into the pocket. Below)
Big sprays come from turning velocity into force and throw water off the tail. Fins out turns, tight snaps. (Steep section, sliding tail, killing speed, but lots of potential energy. Below)
Placement of turns –
Speed conserving turns are done in areas of low potential energy on the wave. The bottom of the wave for bottom turns, the weak shoulder for cutbacks. (Rail buried, weight forward, back foot over larger front fin. Below)
Speed burning turns should be done in areas of high potential energy where you can burn your speed and then “drop” back into the wave regaining velocity. Think a skater stalling at the top of a vert ramp. He can rest for a second and then redrop. Same holds true for surfing, tail throwing turns off the lip kill the majority of your speed, but you’re high on a steep section of the wave, so regain velocity on the drop.
(Lots of spray show that the top turn killed speed, but all the speed you need is in the wave, all potential energy. Below)
Hope that helps… E