That's an oil spout thing from the automotive section at Walmart.
Just put it over the pee hole (erm, for lack of a better term) and test to make sure it comes out the other end

and you're good to go.
Anything long and with a hole large enough in diameter to cover the hole will work. I tried the measuring spoon method and wasn't confident enough using that, so tried this. Modifying a turkey baster will work too.
I was dumb and tried it first time fully clothed, but luckily didn't end up down my leg. Smart thing to do is try it in the shower first.