How do you use 12 vdc to jump start 6vdc for a tractor?

not advisable unless you are badly stuck and if the tractor has no computers

turn the key to the start position before you hook it up and disconnect immediately after it starts Ive seen it done but i am not advising it as i don't know what problems it could cause also don't jump it off something with any computers in it

the thing to do is get a 6 volt charger