Such a motor driver has opto-isolated inputs - you need to run two wires for step and two wires
for direction, the relevant signal and its ground return in each case. Consult the documentation
for the motor driver of course (you did this?). Since the motor driver is opto isolated there
should be no connection between motor supply and arduino at all.
Your guy in the video is connecting 5V to Pul+, Dir+, and EN+. If you look closely you can see the red wire loops between those pins. The Pul- and Dir- are then pulled low to step or change direction, and it doesn't look like he connected anything to disable the drivers.
This is also documented on your eBay page if you just scroll down a bit.
Chagrin:
Your guy in the video is connecting 5V to Pul+, Dir+, and EN+. If you look closely you can see the red wire loops between those pins. The Pul- and Dir- are then pulled low to step or change direction, and it doesn't look like he connected anything to disable the drivers.
This is also documented on your eBay page if you just scroll down a bit.
i connected the 5V to Pul+, Dir+, and EN+ as he did from the arduino power pins, everything worked fine,
i just didnt want to make mistakes and damage so i was extra cautious.
the motor now is rotating but i got a few more questions maybe, i'll post another thread with the specific questions.