I have done what can only be described as a "Noob" mistake. For the past two days I have been customising my main theme and not my child theme. Which in escence means I will lose all my work if I upgrade the theme. This theme is currently in use with the client. I need some advice on how to make my main theme along with it's customisations into a child theme. I have been up and down the forums looking for answers but they always assume that the theme is in an uncustomised state from the begining. My coding experience is at base level so an "Idiot guide" would be appreciated.
Any suggestions would be gratefully received. :)