A Light Sport aircraft pilot attempting to exit the runway reported they attempted to apply the brakes but placed their feet in the wrong position resulting in a taxiway/runway excursion.

Narrative

I own; operate and pilot a Aircraft X; a Light Sport Aircraft. Aircraft X is modeled on the [other aircraft type]; but with a highly sophisticated avionics suite; including ADS-B and autopilot. Aircraft X also has a non-steerable nose wheel with significant caster. Brakes are the only way to effectively control a slow speed taxi. It had been a rough day for flying - anomalous data from the Engine Management System that needed to be resolved; 15 kt. winds; an Airmet for turbulence; and low fuel; in part because my home airport no longer offers 100 LL Avgas for sale. The purpose of the flight was to refuel wherever 100LL was least expensive.Once in the air; I flew to a nearby towered airport and landed there a bit hard; into a 15 kt. wind slightly quartering from the right; I slowed down; but not enough; and turned right at an intersection to taxi off. Aircraft X has a large fin and rudder; so the right turn was made against significant weather vaning resistance from the wind. I was approaching the upwind side of the taxiway at a forty-five-degree angle and the plane wouldn't turn any further. The only thing left was to brake to a stop; but no matter how hard I pushed on the toe brakes; we didn't slow down. And they didn't feel right; my toes were resisted by something solid. Off we went into the rough. Everything seemed intact so I powered up and taxied back onto the ramp. It was only afterward that I saw I had been pushing with both feet on the hanging U shaped structures of the rudder pedals; rather than on the toe brakes. The bottoms of the brakes are anchored to the horizontal tubular rudder bars and are surrounded by the above mentioned structure. (Aircraft X is designed for manufacturing simplicity rather than convenient ergonomics.) In order to fully engage the brakes; it was necessary to raise my heels off the cockpit deck; and in my rush my toes had landed on the structure rather than the brakes. (I have since been advised to move the adjustable rudder pedals closer in order to improve brake and rudder control.)Today's problem; however; had its origin earlier. With the wind so strong; I should have slowed Aircraft X before reaching the downwind side of the intersection and started the turn on the opposite side of the runway from the intersection - and if that were not possible; continued to the next intersection. I now remember this because I have some 340 tail dragger hours in my logbook (all four or more years in the past). This is the safest way to turn a tail dragger effectively in a strong wind; a technique that I now realize is necessary for tricycle gear airplanes with castering nose wheels; as well. Why had I not remembered this? Because flying skills are perishable and because consistently using the brakes to control direction degrades good habits. I plan to revive my tail dragger skills in airplanes with non-steerable nose wheel and significant caster.