Let's take baby steps in learning this.
Heel side to toeside, no transition:
While foiling take your back foot out of the rear footstrap and place it just in front of that footstrap (if strapless just move your back foot forward a bit). Then move your back foot into the other front strap and quickly move your original front foot to the back of the board (if strapless move your feet to roughly where footstraps would be). Do not change direction. You are now riding toside.
You will probably touch down while doing this but with practise you will eventually stay up foiling through this move.
Heel side to toeside jibe:
Turn more and more downwind. Before you go straight downwind (and toward your kite) pull very hard to your front hand to downloop the kite while continuing to turn your board. The downloop is essential to give you a surge of power as you go through the downwind portion of your turn. At first you may want to only do downloops when lightly powered. You will find downloops make this move much easier.
Ideally you ALWAYS downloop when jibing. With practise you will eventually stay up foiling through this move.
Heel side to toeside tack:
While foiling pull on your back hand to bring your kite overhead and then to the other direction. While doing this turn your board upwind (push on your back foot). Keep turning your board all the way around and you will end up toeside going in the other direction. This is a tack without the footswitch. It is more difficult than it sounds. But it is excellent practise for full tacking (with a foot switch). With practise you will eventually stay up foiling through this move.