Here is a well known tune to help you get used to the timing, and playing, of Dotted Quarter notes.
You may notice, that instead of putting the names of the chord notes, beneath the chords, there is now just a letter showing which chord to play, as I hope by now, that you know these chords off by heart.
To make it easier, all of the chords use Whole Notes (four count notes)
Again, there is a video to guide you.