There are actually several types of skateboards but the most common ones are the longboard, cruiser, and carve skateboards. A longboard is usually at least 33 inches. It is a great mode of transportation and works well for cruising around. The cruiser also works well as a mode of transportation but many consider it more beneficial as it has a shorter skateboard, which promotes ease in transporting around.
A rushed take-off might be the problem here. Steps 2-4 of this trick tip could help you out. In order to make your feet “stick” to the board, you have to do the movement fluidly. But don’t stress yourself out! You should rather start with some preliminary exercises until you feel safe while ollieing. It is also important to pull your foot up to your board’s nose in a straight manner to prevent it from spinning.
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.