In the illustration below focus on mm.2 & 4 and make sure to use the same tempo for the 1/8th notes in both measures. You'll see it's where the strong pulses (upward arrows above the notes) occur that differentiates the time signatures.
[IMG]
Screen Shot 2016-02-11 at 1.59.06 PM by
Trevor Burt, on Flickr[/IMG]