You need a timegrapher. They are ~$140 on Amazon for a Weishi 1000, which is fine.
Now to adjust the movement, take a look at this photo. This is what the movement looks like with the back off.
And here is a closeup of the adjustment mechanism
Ignore the Beat Error for now.
The real regulation is done with the lower arm. It works for big adjustments. For fine adjustments, I put a screwdriver on the little pointing nub and turn the screwdriver. It doesn't take much.