There's two kinds of flying foot switch. Front foot and back foot.
The one you see in all the videos is front foot. You keep the front foot in position and move the back foot forward. That's quite hard and takes a lot of timing to get right.
The back foot switch is where you position the back foot in front of the mast, bring the front foot back closer to the back foot, put the old back foot forward, then reposition your new back foot.
The back foot switch is super easy. You can stand around all day with both feet just in front of the mast. You can do it fast or slow. You can do it with smooth fluid movements, or lots of little shuffling steps.
You practice the foot switch by riding in "ski" stance with both feet together in front of the mast. Explore the zone of stability in front of the mast and see where you can put your feet. The zone is bigger with more speed and/or a bigger wing.
The appeal to me of doing the back foot switch is you get a lot of time to explore how the foil feels in lots of different positions and attitudes. Foil rising, falling, carving left right etc. It's loads of fun and leads into front foot switches. You progressively explore the effect of speed on where you can place your front foot.
You might look a bit kooky doing a shuffling switch, but you're less likely to crash. It looks much less kooky than the little scissor jump thing that people do.