Circuit design for DC motor control
The simplest form of motor control is on or off: -



This uses a BC547 transistor fed via a 10k ohm resistor and will accept logic levles as low as 1V. The BC547 then turns on or off a p channel MOSFET capable of supplying decent current to the motor.

Ignore the 12V - this circuit will work at 5V or well over 50V with one slight modification. I won't add anything more in case you are looking for something more sophisticated like PWM control or H-bridge reversing.

H-bridge motor reversing: -


This looks like a good chip for the motor you are planning on using. Note that it has two supplies - one for the motor H bridge (this can be 1.8V up to 11V) and a totally seperate supply for the logic and you'll need to connect this to 1.8V for your logic IO to work properly.