I'm trying to ride switchfoot,not having a great deal of success.

I seem to be putting a lot of pressure on my back foot which makes the board really skatey (not sure if that's a word)

the board gets twitchy and uncontrollable.

Should I move the mast back,move my hips or give up???

thx

A skittish foil usually means your weight is too far back. Move your weight forward. Easiest is to move your back foot forward a bit.

If you are back foot heavy then you could try to move your stance back (ie both feet back a few cm)

Perhaps your mast is too far back, try sneaking it forward a touch.

If you are comfortable riding normal stance, take a look at your foot positions when you are balanced, the spot right between your feet is your center of lift this will be the same riding normal or switch, so just try and replicate this the other direction and you should be close.

[To clarify are you having trouble riding switch (heel side) or do you mean riding same stance but toe side? ]

More than likely your foil is set up wrong as to much back foot or to much front foot is a sign of the foil angle not set right. Can be fixed sometimes with some shims. Changing where you stand or moving the foil in the box is not really the best options and just a well balanced foil set up will do wonders.

I experience the same even if my feet are at the exct same position as when riding normally. It is quite difficult and unconfortable if using straps.
The best is to ride straless and narrow your stance. Also turnig you body (and stance) toward the direction your aiming at (feet closer to rails)

Thx for for all the effort put into the replies

Hopefully there is wind today and I can try all the suggestions

Im a natural foot it's when I place my right foot forward that I find trouble.

Im sorta fine in a twisted stance,but I've just been trying to ride switch.

Or as a an ex younger friend said"I'm an old bastard,I should be playing lawn bowls"

Once the skill is attained, age matters little, but some fitness is required.