With any directional boards, when you need to change direction you'll need to tack or gybe the board to get it pointing in the right direction. A strapless surfboard tack on your kite is a fast way to change direction without going downwind.
Once you get the hang of riding in each direction and good kite control the next step is to learn to tack. It's a matter of balance and perfecting your timing, just follow the tips here and get out there and practice.
This trick is easier to learn in flat water with consistent wind. Once you have it in flat water try practising in choppy conditions for a challenge, then progress into more direction change variations.
Slow down as you approach by starting to edge upwind and slowly drift your kite overhead.
As you get to the start of your direction change you want to carve the board right up into the wind and bring your kite overhead.
If you find you're getting dragged away from your board while you go for the direction change you might find you aren't carving the board up into the wind enough, or slowing down enough through the carve.
As you reach the middle of your direction change the kite should be directly over head and you should just be coming to a stop. You can depower your kite as you go through the direction change to help with balance.
If you find you are losing control at this stage check out your kite position, make sure it's overhead, and your not moving the kite to aggressively.
Use your front foot to drag the board around under your body as you hop to change direction. As you are doing the hop you can start to slowly dive the kite in the new direction. And once your have your feet in the right direction quickly dive the kite in the new direction to start riding.
Practice makes perfect with quick foot positioning. If you find you are sinking through this part of the trick, you may want to try diving the kite harder and earlier to give you some more pull.
As you dive the kite, point the front of the board down wind and ride away. You just nailed your first strapless surfboard tack!