Pruning stopover apple tree

pottering girl

Hi, I have looked at videos but can't determine how to prune my stepover apple.  It has quite a few long laterals from last season all the way along, I think I should be cutting these back to the first bud nearest the main structure, could someone more knowledgeable confirm please.  Also I think I should be cutting the main arms back by a third every year, could someone confirm that too please.

pansyface

Perhaps this description with drawings and photos might make more sense. Note the time of year.

https://www.choicegardeningclub.co.uk/apple-stepover

pottering girl

That's perfect, thanks for your help..