I need to know how to time a honda crf230?

i need to know how to time a crf 230 because i let my cousin ride it and he got it so hot that it jumped time and i went to the honda shop they told me that it would cost 200 dollars to time it so i wnat to try to do it my self but i cant find any thing on the internet on how to time it so if someone out their know how to time it please could u tell me how thank u