Flatwards ! – Peach and Nectarines for walls are very easy to train , just think logically and use the tree’s natural tendency to branch.
Use those shoots that are in the right place and remove those that are not.
Only prune in May or at the time of harvest.
Do not try to bend or force growth by pruning, this will create more wounds to let in disease.
This method is called ‘extension pruning’ it does not involve heavy cutting back, which is disastrous for stone fruit as it is a sure way to let in bacterial canker.
I leave these sketches to do the explaining -All we do with a maiden tree is to prune out the centre in May; training the two shoots below outwards, if you get stuck ,add a comment so I can edit to help you.