I am doing this with a MOSFET, with what I have read is the easiest way to do this. I am doing it with the IRF520 MOSFET board.
I might be an idiot mechanical engineer right now, but when I got the wires that connect to the solenoid there were 3 wires, red, black and white. I assumed that was power ground and trigger of some kind. I am just not sure how to connect everything to the board so that I can power it properly. Any help would be greatly appreciated.
According to datasheet, coil power is 2 Watts, 2W / 12V = 167mA.
Which Arduino are you using? IRF520 won't work with 3.3V gate voltage, you need a logic level MOSFET with low threshold voltage (< 1V).