To get higher ollies, I would suggesting resting your back foot on the very end of the tail and the front foot in the middle of the deck to allow for more slide. Popping as hard as you can and catching your board in the groove of the nose with you ankle practically resting in the groove will level the board out in the air. after this initial movement slide you feet back to the bolts on the tail and nose to ensure a clean landing.
In 1982, while competing in the Rusty Harris contest in Whittier, California, Rodney Mullen debuted an ollie on flat ground, which he had adapted from Gelfand's vertical version by combining the motions of some of his existing tricks. Mullen used a "see-saw" motion, striking the tail of the board on the ground to lift the nose, and using the front foot to level the board in mid-air.[2] While Mullen was not initially impressed with his flat ground ollie, and did not formally name it, he realized it opened up a second, elevated plane on which to perform tricks.[citation needed]
The board is shaped like a cup in the center, and has whale tails on both ends, designed to make tricks easier to do. The blue stain on the board looks like the picture. It has a semi flat finish with no lacquer top coat. The underside is plain which allows the owner to add stickers and graphics if they want but they look great just the way they are.
The following descriptions cover skateboard parts that are most prevalent in popular and modern forms of skateboarding. Many parts exist with exotic or alternative constructions. A traditional complete skateboard consists of the deck (often with griptape applied on top to enhance traction), trucks (with urethane bushings), wheels (with sealed bearings), bushings, nuts and bolts to fasten the truck and wheel assembly to the bottom of the deck. Older decks also included plastic parts such as side, tail, and nose guards.
Slam your back foot down on the tail of your skateboard as hard as you can. At that moment, you want to also jump into the air, off of your back foot. This part is key and takes practice. The trick is in getting your timing right. You want to slap the skateboard’s tail down, and as it hits the ground, jump off of that foot into the air. Make sure to pull that back foot high into the air. It's a quick, snapping motion.
So the proper foot placement for the ollie is with the ball of your back foot horizontal on the tail of your skateboard.  And your front foot centered on your board right behind the front trucks.  You may find that moving your feet around in different positions are more comfortable.  This is fine,  everybody can learn how to skateboard their own way.
4 amazing skateboards in one nice lot. 1. 1990's Tony Hawk Conplete Skateboard, original falcon 3 design. With Rekon trucks and firelite classic wheels. 2. Sk8mafia Lucero deck. Signed by John Lucero. Brand new deck. 3. 1031 deck signed by entire team on a brand new creepy crawl deck. 4. Brand new super rare Big Mess deck with Blast design. This deck is extremely rare and is a must have for any collector. Both the signed decks are personalized to a guy named Jason that owned a skate shop here in Grant's Pass Or. Those guys were on his wall for a long time before he went out of business. If you have any questions or concerns please let me know. Thanks for looking. Steve