How to ?

I just bought a totally restored 1978 250. The delivery guy dropped it off while we were out and put it in the garage. This is my first Husqvarna, my first dirt bike and my first 2 stroke and did I mention I'm 67 ? There's no owners manual so I don't know which direction to put the petcock to start it ! Now that's tragic ! Everything I own points straight down to start so I assume this does but I don't want a heart attack if I'm wrong. I looked all over the internet and I can't find an owners manual. Can anybody help ?

check under our technical reference section and you will be able to print or download all the info you could want for the ol girl....yes, down is the on position

As I recall, Husky usually positioned the lever to the inside so it wouldn't get moved by the riders leg, I'm guessing.
Remember the petcock is left hand thread and the nut to the tank is right hand. The trick is to loosen one and tighten the other until the petcock is tight and positioned where you want it. If you only tighten the nut to the tank it's hard to get it in the right position and it will most likely leak because the petcock isn't sealing to the tank outlet.